Enzymes share two key characteristics with all other catalysts - First, they speed up chemical reactions without being consumed or irreversibly changed by the process and secondly, they also speed up reactions while maintaining the chemical balance between reactants and products.
A drop in the activation energy barrier occurs when an enzyme is present. The quantity of product molecules stays constant. However, there will be a rise in the reaction rate, or the number of product molecules created per unit time. The products' final energy is unchanged from an uncatalyzed process. The reaction's rate quickens. As a result, there are still the same amount of reactant molecules. The amount of substrate molecules converted to products per unit of time will grow, but not the reaction rate. The reactants' initial energy is unchanged from an uncatalyzed reaction.
The free energy of the reactants or products is unaffected by enzymes. Instead, enzymes reduce the energy of the unstable transition state, which reactants must proceed through in order to become products.
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How do I round 999999 to 3 sig figs
The number of significant figures in a result simply refers to the number of figures that are known with certainty. Here,
1000000 is 999999 rounded to three significant figures.
What is the best way to round a number to three significant figures?Significant figures are digits of value that have meaning in terms of measurement resolution. In chemistry, they are also known as significant figures. All of the experimental measurements are subject to some degree of uncertainty.The number of significant figures in a result is simply the number of figures that are reliably known.A number is rounded to three significant figures in the same way that it is rounded to three decimal places. For three digits, we start counting from the first non-zero digit. The final digit is then rounded. We use zeros to fill in any remaining spaces to the right of the decimal point.To learn more about significant figures refer to :
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In science class, Ruthie and Heena are conducting a science experiment. They wanted to find out which type of fertilizer would make the plants grow the fastest. The added equal amounts of soil to four identical pots. In three of the pots they added the different types of fertilizer to the soil. They did not add any fertilizer to the fourth pot. Over the next two weeks they measured the height of each of the plants. What is the purpose of the fourth pot that contained no fertilizer?
The purpose of the fourth pot that contained no fertilizer is to observe the actual growth of the plant without any fertilizers.
Fertilizers paintings by means of imparting vital vitamins to developing plants, bushes, and veg, as a form of multi-nutrition or meal substitute for the plant international. Many fertilizers additionally improve the way the soil works by helping it to maintain water higher and allowing air to drift freely, which is right for roots.
Fertilizers increase their growth via the application of fertilizer remedies. development in plant boom was notably discovered by means of the application of each natural and inorganic source of mineral vitamins.
The more fertilizer a crop gets, the faster it grows. We understand if a crop is supplied with too little fertilizer, plant increase response is negative; however if fertilizer charges are immoderate, plant increase slows and there is a potential for root harm or demise from high fertilizer salts.
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A 100.0-mL aliquot of 0.200 M aqueous potassium hydroxide is mixed with 100.0 mL of 0.200 M
aqueous magnesium nitrate.
(a) Write a balanced chemical equation for any reaction that occurs.
(b) What precipitate forms?
(c) What mass of precipitate is produced?
(d) Calculate the concentration of each ion remaining in solution after precipitation is complete.
i mostly need help on the last one
The balanced equation of the reaction is:
2 KOH (aq) + Mg(NO₃)₂ ---> Mg(OH)₂ (s) + 2 KNO₃ (aq)The precipitate formed is magnesium hydroxide.
The mass of precipitate produced is 0.58 g.
The concentration of the ions remaining in the solution are:
[Mg²⁺] = 0.05 M
[NO₃⁻] = 0.1 M
What is the balanced equation of the reaction of aqueous potassium hydroxide and aqueous magnesium nitrate?The balanced equation of the reaction of aqueous potassium hydroxide and aqueous magnesium nitrate is given below:
2 KOH (aq) + Mg(NO₃)₂ ---> Mg(OH)₂ (s) + 2 KNO₃ (aq)
Magnesium hydroxide is obtained as a precipitate in the reaction above.
The mass of precipitate produced is calculated as follows:
moles of KOH (aq) reacting = 0.200 * 100 / 1000 = 0.02 moles
moles of Mg(NO₃)₂ reacting = 0.2 * 100 / 1000 = 0.02 moles
From the equation of reaction, KOH is the limiting reagent.
Moles of precipitate formed = 0.02 / 2 = 0.01 moles
molar mass of Mg(OH)₂ (s) = 58 g/mol
Mass of precipitate formed = 0.01 * 58
Mass of precipitate formed = 0.58 g
Moles of Mg(NO₃)₂ remaining = 0.02 - 0.01 = 0.01 moles
total volume of solution = 200 mL or 0.2 L
The concentration of each ion remaining in the solution is as follows:
[Mg²⁺] = 0.01 / 0.2 = 0.05 M
[NO₃⁻] = 0.01 * 2 / 0.2 = 0.1 M
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BRAINLIEST LOTS OF POINTS | One molecule of bromine (Br2) and two molecules of potassium chloride (KCl) combine in a reaction. How many atoms are in the products?
First, write out the equation.
Balance the equation.
Count atoms in the product.
What is the answer?
Answer:
6 atoms
Explanation:
Br2 + 2KCl = 2KBr + Cl2
2KBr = 4 atoms
Cl2 = 2 atoms
total 6 atoms
Chemical reaction between bromine and potassium chloride is 2 KCl +Br₂[tex]\rightarrow[/tex] 2 KBr +Cl₂. There are 6 atoms in the product .
What is a chemical reaction?Chemical reactions are defined as reactions which occur when a substance combines with another substance to form a new substance.Alternatively, when a substance breaks down or decomposes to give new substances it is also considered to be a chemical reaction.
There are several characteristics of chemical reactions like change in color, change in state , change in odor and change in composition . During chemical reaction there is also formation of precipitate an insoluble mass of substance or even evolution of gases.
There are four types of chemical reactions:
1) combination reaction
2)decomposition reaction
3) single displacement reaction
4) double displacement reaction
During chemical reactions atoms are rearranged and reactions are accompanied by an energy change as new substances are formed.
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Look at the wave in the picture. If it has a wavelength of 2 cm, how far apart are points A and B? How do you know?
From the description, we can see that A and B is one wavelength thus the distance between the points is also 2 cm.
What is the wavelength?We can define the wavelength as the distance between two successive crests or the distance between two successive troughs. The crests are above the chart and the troughs are below the chart.
In this case, we have been asked to obtain the distance between A and B. Knowing that the points A and B are two successive crests and we have been told that the wavelength is 2 cm thus the distance between A and B is 2cm.
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Food provides calories needed by the body for energy. However, the body must use energy between meals when food is not consumed. What is the most likely response of the body when more energy is needed than the calories that have been consumed?.
When more energy is needed than the calories that have been consumed to release energy from lipids stores throughout the body.
What do food calories mean?Calories are the unit of energy used by your body during food digestion and absorption. A meal might provide your body extra energy if it contains more calories. Your body stores extra calories as body fat if you eat more food than you need. Even foods without fat might have a significant number of calories.
How can I burn calories?The most effective way to burn calories is through aerobic exercise, which includes sports like swimming, cycling, and walking. Include at least 30 minutes of exercise each day as a general goal.
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is the product the same with the original material? why compare the materials before and after exposing it (soaked and exposed potato)
the answer is no
Explanation:
the soaked potato is already immersed in water and is likely to get spoilt few days before the exposed potato.because a liquid medium has already been used. while the exposed potato still possesses its same properties as before
Saltpeter is a potassium salt. It is 13.9% nitrogen, 38.6% potassium and 47.5% oxygen. What is its empirical formula?
Considering the definition of empirical formula, the empirical formula of the potassium salt is KNO₃.
Definition of empirical formulaThe empirical formula is the simplest expression to represent a chemical compound, which indicates the elements that are present and the minimum proportion in whole numbers that exist between its atoms, that is, the subscripts of chemical formulas are reduced to the most integers. small as possible.
Empirical formula in this caseIn this case, you know:
Nitrogen (N): 13.9%Potassium (K): 38.6%Oxygen (O): 47.5%Assuming a 100 grams sample, the percentages match the grams in the sample. So you have:
Nitrogen (N): 13.9 gramsPotassium (K): 38.6 gramsOxygen (O): 47.5 gramsThen it is possible to calculate the number of moles of each atom in the molecule, taking into account the corresponding molar mass:
Nitrogen (N): [tex]\frac{13.9 grams}{14 \frac{g}{mol} }[/tex]≅ 1 molePotassium (K): [tex]\frac{38.6 grams}{39.1 \frac{g}{mol} }[/tex]≅ 1 moleOxygen (O): [tex]\frac{47.5 grams}{16 \frac{g}{mol} }[/tex]= 2.97≅ 3 molesThe empirical formula must be expressed using whole number relationships, for this the numbers of moles are divided by the smallest result of those obtained. In this case:
Nitrogen (N): [tex]\frac{1 mole}{1 mole}[/tex]≅ 1Potassium (K): [tex]\frac{1 mole}{1 mole}[/tex]≅ 1Oxygen (O): [tex]\frac{3 mole}{1 mole}[/tex]= 3Therefore the K: N: O mole ratio is 1: 1: 3
Finally, the empirical formula is K₁N₁O₃= KNO₃.
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1. How does the atomic structure of sodium determine its uses and functions?
Answer:octahedral coordination around Na + and Cl − centers.
Why do we take a weighted average of all naturally occurring isotopes instead of adding protons and neutrons?
The average atomic mass of an element, which is shown in the element's box on most periodic tables, is the sum of the atomic masses of all its isotopes (at least, the isotopes that exist naturally). The average, nevertheless, is a weighted average.
What is the weighted average of isotopes that are found naturally?The weighted average of an element's naturally occurring isotopes' atomic masses is that element's atomic mass.
The atomic mass is the average of the atomic masses of all the isotopes of a given element, weighted by their relative abundance in nature. Because various isotopes have different masses, it is a weighted average.
Due to its objectivity towards intermediate values and given average value, which most observations fall within, a weighted average is utilised. Furthermore, it is unaffected by extreme values or outliers. Outliers have an effect on the basic average.
Because there is no standard mass for an element, this is done.
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the following reaction was performed in a sealed vessel at 731 ∘c : h2(g) i2(g)⇌2hi(g) initially, only h2 and i2 were present at concentrations of [h2]
The equilibrium constant for the reaction at the given temperature is 273.03.
What is the equilibrium constant, Kc, for the reaction at the given temperature?The equilibrium constant, Kc, for the reaction at the given temperature is calculated as follows:
Making an ICE table from the equation of the reaction and the given concentration values:
H₂ (g) + I₂ (g) ⇌ 2 HI (g)
I 3.85 2.35 0
C 2.30 2.30 2 * 2.30
E 1.55 0.05 4.60
Kc = [HI]² / [H₂] * [I₂]
Kc = (4.60)² / (1.55) * (0.05)
Kc = 273.03
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Complete question:
The following reaction was performed in a sealed vessel at 760 ∘C:
H₂ (g) + I₂ (g) ⇌ 2 HI (g)
Initially, only H₂ and I₂ were present at concentrations of [H₂] = 3.85M and [I₂] = 2.35M . The equilibrium concentration of I₂ is 0.0500 M .
What is the equilibrium constant, Kc, for the reaction at this temperature?
If the [H*] changed from [1 x 10-7] to [1 x 10-4], what is the new [OH-]?
01x 10-4
01x10-3
01 x 10-10
01x 10-7
The new concentration of hydroxide ions [OH-] is calculated as 1 x [tex]10^{-10}[/tex] M if the [[tex]H^{+}[/tex]] changed from [1 x [tex]10^{-7}[/tex]] to [1 x [tex]10^{-4}[/tex]] during the concentration change.
How do you determine H+ using pH?By “undoing” the common logarithm by exponentiating both sides with base 10 to obtain [[tex]H^{+}[/tex]] = 10pH.
How can I determine pH?You need to know the hydronium ion concentration in moles per litre to determine the pH of an aqueous solution (molarity). The formula pH = - log is then used to get the pH. [H3O+].
Concentration of [tex]H^{+}[/tex] ions = [[tex]H^{+}[/tex]] = 1 x [tex]10^{-7}[/tex]
When concentration of [[tex]H^{+}[/tex]] ions changed to 1 x [tex]10^{-4}[/tex] M
[[tex]H^{+}[/tex]] = 1 x [tex]10^{-4}[/tex] M
The pH of the solution will further change to:
pH = -log [[tex]H^{+}[/tex]]' = -log [1 x [tex]10^{-4}[/tex]] = 4
pH + pOH = 14
pOH = 14 - 4 = 10
And we know that:
pOH = -log [[tex]OH^{-}[/tex]]
10 = -log [[tex]OH^{-}[/tex]]
[[tex]OH^{-}[/tex]] = 1 x [tex]10^{-10}[/tex] M
Important IdeasIf the pH of the solution is known, it is possible to compute the hydrogen ion concentration in a solution, [H+], in mol L-1.
The negative logarithm (to base 10) of the hydrogen ion concentration in mol L-1 is used to calculate pH. pH equals -log10[H+]
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Which separation method is used in making coffee at home
Answer:
Filtration eg coffee maker
suppose you determine that a particular plant consumes 37.8 g of co 2 in one week. assuming that there is more than enough water present to react with all of the co 2, what mass of glucose (in grams) can the plant synthesize from the co 2? molar mass co 2
mass of glucose (in grams) can the plant synthesize from the co 2 is 25.8g
What mass of glucose (in grams) can the plant synthesize from the co 2?molar mass of [tex]CO_{2}[/tex]= 44.01 g/mol
molar mass of [tex]C_{6} H_{12} O_{6}[/tex] =180.18g/mol
[tex](g)CO_{2}-- > (mol)CO_{2} --- > (mol)C_{6} H_{12} O_{6}-- > (g)C_{6} H_{12} O_{6}[/tex]m
[tex]\frac{1 mol CO_{2} }{44.01 g CO_{2}}[/tex] [tex]\frac{1 mol C_{6} H_{12} O_{6} }{ 6 mol CO_{2}}[/tex] [tex]\frac{180.18 g C_{6} H_{12} O_{6} }{ 1 mol C_{6} H_{12} O_{6} }[/tex]
37.8g x [tex]\frac{1 mol CO_{2} }{44.01 g CO_{2}}[/tex] x [tex]\frac{1 mol C_{6} H_{12} O_{6} }{ 6 mol CO_{2}}[/tex] x [tex]\frac{180.18 g C_{6} H_{12} O_{6} }{ 1 mol C_{6} H_{12} O_{6} }[/tex]
= 25.8g [tex]C_{6} H_{12} O_{6}[/tex]
mass of glucose (in grams) can the plant synthesize from the co 2 is 25.8g.
What precisely is glucose?It is a monosaccharide because it is the most basic type of carbohydrate. It has one sugar, thus this indicates. It's not by itself. Galactose, ribose, and fructose are examples of additional monosaccharides. One of the body's preferred sources of fuel in the form of carbs is glucose, along with fat.
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Calculate the pH of each of the following solutions from the information given.
(a) [H+] = 4.80 *10^-2 M
(b) pOH = 4.71
(c) [OH - ] = 9.61 *10^-3 M
(d) [H+] = 1.37 *10^-8 M
( a ) The pH of 4.8 × [tex]10^{-2}[/tex] M solution is 1.3 ..
( b ) The pH of 4.71 pOH solution is 9.29
( c ) The pH of 9.61 × [tex]10^{-3}[/tex] M hydroxide ion solution is 11.98.
( d ) The pH of 1.37 × [tex]10^{-8}[/tex] M solution is 8.17
( a )
pH = - ㏒ [ [tex]H^{+}[/tex] ]
pH = - ㏒ [ 4.8 × [tex]10^{-2}[/tex] M ]
pH = 1.3
Therefore , the pH of 4.8 × [tex]10^{-2}[/tex] M solution is 1.3 .
( b )
The pOH = - ㏒ [ [tex]OH^{-}[/tex] ]
Given pOH = 4.71
So put the value of pOH .
pH + pOH = 14
pH = = 14 - pOH = 14 - 4.71 = 9.29
Therefore , the pH of 4.71 pOH solution is 9.29 .
( c )
The pOH = - ㏒ [ [tex]OH^{-}[/tex] ]
Given concentration of hydroxide ion = 9.61 × [tex]10^{-3}[/tex] M
So put the value of concentration of hydroxide ion in equation 1
pOH = - ㏒9.61 × [tex]10^{-3}[/tex] M
pOH = 2.01
pH + pOH = 14
pH = = 14 - pOH = 14 - 2.01 = 11.98
Therefore , the pH of 9.61 × [tex]10^{-3}[/tex] M hydroxide ion solution is 11.98.
( d )
pH = - ㏒ [ [tex]H^{+}[/tex] ]
pH = - ㏒ [ 1.37 × [tex]10^{-8}[/tex] M ]
pH = 8.17
Therefore , the pH of 1.37 × [tex]10^{-8}[/tex] M solution is 8.17
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How would the amount of water produced compare if you ignited a very large balloon of hydrogen and oxygen instead of a very small balloon filled with the same reactants (hydrogen and oxygen)?
The amount of water that we get from the large balloon is greater than the amount of water that we get from the small balloon.
What is the ratio of the reactants in water?
We know that water is composed of hydrogen and oxygen. Let us recall that the ratio of the water and the oxygen that form the water molecule is fixed irrespective of the volume of the water that we use for the reaction.
If we compare if you ignited a very large balloon of hydrogen and oxygen instead of a very small balloon filled with the same reactants, we would notice that the amount of water that is formed from the large balloon of hydrogen and oxygen is greater than that produced from a very small balloon filled with the same reactants.
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what is the mass of the block of iron illistrated below
The mass of the iron object is 787.4 g.
What is density?The term density has to do with the mass per unit volume of the object. This implies that when we divide the mass of the object by the volume of the object, we get the density of the object.
We also have to note that the density is an intrinsic property of an object could be used as a means that can be harnessed in the process of trying to identify the unknown material that we have.
In this case we have the thorough depiction of the iron as we can see from the image attached and we want to find the mass of the object.
Volume of iron = 2 cm * 10 cm * 5 cm = 100 cm³
Density of iron = 7.874 g/cm³
Mass of iron = Volume * density = 100 cm³ * 7.874 g/cm³ = 787.4 g
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!PLS URGENT 50 POINTS! Determine the pressure change when a constant volume of gas at 1.5 atm is heated from 18 °C to 32 °C.
things in common of non-metals
Answer:
Non-metals are brittle. ...
Non-metals are bad conductors of heat and electricity (except graphite).
Non-metals are non-lustrous (dull) and cannot be polished (except iodine).
Non-metals may be solids, liquids or gases at room temperature.
Non-metals are neither tough nor strong.
Thing in common of non- metals are :
The elements that absorb or gain electrons to get negative ions square measure referred to as non-metals. In their outmost shell, non-metals typically have four, 5, half dozen or seven electrons.
High inclination and high ionisation energies square measure characteristics of non-metals.
Because of these characteristics, non-metals ofttimes gain electrons after they move with different substances to make valence bonds.
Non-metals often have smaller atoms than do metals. The atomic sizes of non-metals determine a number of their other characteristics.
A high electronegativities are seen in non-metals. This indicates that non-metal atoms exhibit a significant propensity to attract more electrons than they would ordinarily have.
A high electronegativities are seen in non-metals. This indicates that non-metal atoms have a strong propensity to retain their existing electrons.
As opposed to non-metals, which can give up one or more electrons to metals relatively easily, metals can easily form positively charged ions and conduct electricity.
Very little electrical conductivity is displayed by non-metals.
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Tissues are composed of groups of:
Balance the following the chemical equation: _ Na2O + _ CaBr2 → _ NaBr + _ CaO
The balanced form of the chemical equation is as follows:
Na₂O + CaBr₂ → 2NaBr + CaO
What is a balanced chemical equation?A chemical equation is a symbolic representation of a chemical reaction where reactants are represented on the left, and products on the right.
A chemical equation is said to be balanced when the number of atoms of each element on both sides of the equation is the same.
To balance a chemical equation, we make use of coefficients, which are numbers placed in front of the elements to make the atoms equal.
According to this question, sodium oxide reacts with calcium bromide as follows:
Na₂O + CaBr₂ → 2NaBr + CaO
The above equation is said to balanced because the following atoms are equal on both sides of the equation:
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a detailed description of the steps in a reaction, including information on the relative order and rate of bond formation and cleavage, is called a reaction .
A detailed description of the reaction steps, along with information on the relative order and cost of forming and breaking bonds, is called a reaction mechanism.
Information is an important stimulus for the recipient in some contexts. Records are entered and stored on a computer but are commonly referred to as statistics. The definition of statistics is news or know-how acquired or provided. A data instance is what is provided to a person requesting information about something. Statistics is a generalized concept that refers to something that has the power to speak. At its most essential level, facts represent the translation of the perceptible. Proper record keeping is believed to improve decision-making, complement productivity, and give employers a competitive advantage that knows more than their competitors. Use facts.
People use the information to find meaning in a variety of situations. Sometimes they use notes as a tool to do real things (eg, to gain abilities or achieve goals). In other cases, statistics are used for cognitive purposes (eg generating ideas).
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Write a balanced overall reaction from these unbalanced
half-reactions.
Sn —> Sn2+
Ag+ + Ag
Answer:
Sn°(s) + 2Ag⁺(aq) => Sn²⁺(aq) + 2Ag°
Explanation:
Sn°(s) => Sn²⁺(aq) + 2e⁻ [oxidation]
2Ag⁺(aq) + 2e⁻ => 2Ag°(s) [reduction]
Sn°(s) + 2Ag⁺(aq) => Sn²⁺(aq) + 2Ag°
Which type of force exists as a result of positive and negative charges?
A. Electromagnetic
B. Weak nuclear
C. Strong nuclear
D. Gravitational
The type of force exists as a result of positive and negative charges is C. Strong nuclear.
What does the strong nuclear force do?
It is known to often holds Quarks, the fundamental particles that make up protons and neutrons of the atomic nucleus, are held together by the strong force, which also keeps protons and neutrons together to form atomic nuclei.
Note that Positively charged protons as well as neutrally charged neutrons are created when the strong nuclear force brings together positively and negatively charged quarks. In the atomic nucleus, protons and neutrons are also held together by the strong nuclear force.
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when a substance undergoes boiling, do the particles move faster or slower?
Heat causes a liquid's particles to gain more energy, which causes them to move more quickly and expand the liquid.
When water boils, what happens to the water molecules?The heat energy used to boil the water is transmitted to the water molecules, which cause them to start moving more swiftly. The energy of the molecules eventually becomes too great for them to remain bound together as a liquid. This causes them to condense into gaseous water vapor molecules, which rise to the surface as bubbles as well as move through the air.
How much thermal energy is there?Thermal energy is the term used to describe the energy present in a system that determines its temperature. The movement of thermal energy is heat.
Briefing:The particles in a liquid gain more energy as it is heated and travel more quickly, causing the liquid to expand. As the liquid becomes warmer, the surface's most energetic particles vaporize and flee.
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please can someone help me define atomic number, Mass number and isotopy urgently
Is there a periodic trend in oxidation strength of the halogens?
Explanation:
As the halogens become less reactive down the group, their oxidising ability decreases. Remember that oxidation is a gain of electrons. Halogens become less oxidising as you move down the group as it is more difficult to gain an electron.
Adult fireflys are active primarily during twilight, which is during dawn and dusk. This kind of animal is classified as ___________.
A)
a dawn and dusk forager
B)
crepuscular
C)
diurnal
D)
nocturnal
E)
perennial
Answer:The answer would be crepuscular! I actually study fireflies as a living after school!
please help with this need it in 6 hours
1.)in the thermit reaction 2Al + Fe2o3= al2o3 + 2 fe. what is the mass of aluminium powder is needed to react with 8.0g of iron (3) oxide
2.) what mass of magnesium sulphate crystals can be made from14.0g of magnesium carbonate and an excess of dilute sulphuric acid
3.) what mass of calcium oxide is formed when 25g of calcium carbonate is decomposed by heat?
4.) Lead (ii) oxide PbO, reacts with hydrogen to for lead and steam. calculate the mass of lead in formed when 446g of lead (ii) oxide is reduced in this way.
5.) what volume of gas is given off when excess calcium carbonate is added to 50cm cube of 2.0M by hydrochloric acid , if the gas volume is measured at s.t.p.?
1) Mass of aluminum powder is 2.7 g.
2) Mass of magnesium sulfate is 19.9 g.
3) Mass of calcium oxide is 14g.
4) Mass of lead 412.2 g.
1) In the thermite reaction :
2Al + Fe₂O₃ -----> Al₂O₃ + 2Fe
mass of Fe₂O₃ = 8.0 g
molar mass of Fe₂O₃ = 159.6 g/mol
number of moles = mass / molar mass
= 8.0 g / 159.6 g/mol
= 0.050 moles
1 mole of Fe₂O₃ react with 2 mole of Al ,
0.050 Fe₂O₃ moles react with 2 × 0.050 = 0.1moles of Al
number of moles of Al = mass / molar mass
mass of Al = no. of moles × molar mass
= 0.1 mol × 27 g/mol
= 2.7 g
Thus, the mass of aluminum powder is needed to react with 8.0 g of iron (III) oxide is 2.7 g
2) the reaction is :
MgCO₃ + H₂SO₄ -----> MgSO₄ + CO₂ + H₂O
mass of MgCO₃ = 14.0 g
no. of moles of MgCO₃ = mass / molar mass
= 14 g / 84.3 g/mol
= 0.166 moles
1 mole of MgCO₃ produced 1 mole of MgSO₄,
0.166 mole of MgCO₃ produced 0.166 mole of MgSO₄
mass of MgSO₄ = 120.3 g/mol
no. of moles of MgSO₄ = mass / molar mass
mass of MgSO₄ = no. of moles × molar mass
= 0.166 mol × 120.3 g/mol
= 19.9 g
Thus, mass of magnesium sulfate crystals can be made from14.0g of magnesium carbonate and an excess of dilute sulfuric acid is 19.9 g
3) the reaction is :
CaCO₃ -----> CaO + CO₂
mass of calcium carbonate = 25 g
molar mass of CaCO₃ = 100 g/mol
no. of moles of = mass / molar mass
= 25 / 100
= 0.25 mol
0.25 moles of CaCO₃ produced 0.25 moles of CaO
molar mass of CaO = 56 g/mol
mass of CaO = no. of moles × molar mass
= 0.25mol × 56 g/mol
= 14 g
the mass of CaO produced 14 g.
4) PbO + H -----> Pb + H₂O
mass of PbO = 446g
no. of moles = mass / molar mass
= 446 g / 223.3 g/mol
= 1.99 mols
1.99 moles of PbO produced 1.99 moles of Pb
molar mass of Pb = 207.2 g/mol
mass of Pb = no. of moles × molar mass
= 1.99 mol × 207.2 g/mol
= 412.2 g
Thus, Lead (ii) oxide PbO, reacts with hydrogen to for lead and steam. calculate the mass of lead in formed when 446g of lead (ii) oxide is 412.2g.
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Which metal is likely to be more reactive? Mg or Rb
please explain why
Answer: Rb is more reactive
Explanation: The reason rubidium is more reactive is because it loses its valence electron more readily than Mg does.
Answer:
Rb
Explanation:
Mg has 2 valence electrons to loose vs Rb has 1 valence electron to loose.
Rb wins because losing 1 electron is easier than having to lose 2, which means Rb is more reactive ("ready" to react).