Answer:
Incorrect
Explanation:
Given that,
The mass of a boulder, m = 22 kg
We need to find the weight of the student in pounds.
We know that,
1 pound = 454 g
or
1 g = (1/454 pounds)
22 kg = 0.022 grams
So,
0.022 grams = [tex]\dfrac{0.022}{454}\ pounds[/tex]
= 0.000048 pounds
The student says the weight is 0.048 pounds. It means he was incorrect.
Gallium (Ga, 69.723 g/mol) is a metalloid obtained from its salts during the smelting of ores of other elements, like Zinc, Ga has broad applicability in the electronics industry. It is also used as a safe replacement for mercury in thermometers as it melts at 29.8 oC and has a heat of fusion of 5.59 kJ/mol. What is the entropy change of of gallium in as it melts when placed on a surface at 29.8 oC?
Answer:
4.255 J/ K
Explanation:
Given data :
mass of Gallium = 16 gm
molar mass = 69.723 g/mol
hence no of moles = 16 / 69.723 = 0.23 moles --------- ( 1 )
Δh ( heat fusion ) = 5.59 KJ/mol
Temperature = 29.8°C = 302.8 k
Determine the entropy change of gallium
Δs ( entropy change ) = heat fusion / temperature
= ( 5.59 * 1000) J/mol / 302.8 = 18.46 J/k*mol
Hence entropy change of gallium
= Δs * no of Gallium moles
= 18.46 * 0.23 = 4.255 J/ K
Help!!
Which of the following tends to have increased solubility from increased pressure?
A gas in a liquid.
a liquid in a solid.
a solid in a gas.
A solid in a liquid.
Answer:
a solid in a gas
Explaination:
because soild will take a long while to dissolve into liquid by heating the soild with gas it will disslove quicker
Is that flirting? I'm not sure and I really need to know-
Answer:
I mean ig it is, but i dk
Explanation:
what is the first element in the periodic table?
Answer:
the first element on the table is Hydrogen
Why is it important for some skateboarding ramps to be tall? Use the terms "potential energy" and "kinetic energy" in your answer. plsssssss help meeee Plzzz in kids words
Explanation:
Yw ❤
Shorter people have a lower center of gravity. Taller people have a higher center of gravity. A lot of skateboarding tricks depend on the center of gravity.
What is kinetic energy?
Kinetic energy is a form of energy it possess when any object or person is in motion . It can be defined as the work needed to be done to produce a motion in a object from rest position.
If we want to acceleration in an object then we must apply a force on a object to give motion so we can say that we required to do work for acceleration and then we can say that required is equal to kinetic energy.
Mathematically
Kinetic energy =1/2mv^2
Where
m = mass of object.
v = velocity of object
Kinetic energy is vector quantity it means that it have both i.e magnitude and vector.
S.I unit of Kinetic energy is Joule.
Therefore, Shorter people have a lower center of gravity. Taller people have a higher center of gravity. A lot of skateboarding tricks depend on the center of gravity.
Learn more about kinetic energy here:
https://brainly.com/question/12669551
#SPJ2
Why glucose (monosaccharide) and maltose (disaccharide) give positive Benedict test?
Answer:
please give me brainlist and follow
Explanation:
Substance in water + 3 mL Benedict's solution, then boil for few minutes and allow to cool. The common disaccharides lactose and maltose are directly detected by Benedict's reagent because each contains a glucose with a free reducing aldehyde moiety after isomerization.
Glucose and maltose give a positive Benedict test because they have a free carbonyl group to undergo oxidation.
Explanation:
The monosaccharides are sugars that cannot be further hydrolyzed into simpler sugars like glucose, fructose, ma, etc.The disaccharides are sugars that on hydrolysis give two monosaccharide units like sucrose, lactose, maltose, etc.The polysaccharides are sugars that on hydrolysis give more than two monosaccharide units like sucrose, lactose, maltose, etc.Reducing sugars are which have a free carbonyl group that oxidizes into a carboxylic acid and reduces Benedict reagent like glucose, maltose, etc.Non-reducing sugars which don't have a free carbonyl group like sucrose, all polysaccharides, etc.Benedict test is a chemical test performed to test the presence of reducing sugars.The Benedict reagent is a complex made up of sodium citrate, sodium carbonate, and copper sulfate pentahydrate.The positive test for reducing sugar will be the red coloration of the solution due to the formation of copper(II) oxide.So, from this, we can conclude that glucose and maltose give a positive Benedict test because they have a free carbonyl group to undergo oxidation.
Learn more about carbohydrates:
brainly.com/question/3950786?referrer=searchResults
brainly.com/question/1157431?referrer=searchResults
5. Choose the best description of a reversible reaction.
a reaction that occurs in both directions at the same time
a reaction that has used up all the reactants and has stopped
a reaction that can only proceed to the right
a reaction that can only proceed to the left
Answer:
A reaction that can only move towards the right.
Explanation:
For a reversible reaction when one of the products of the reaction is removed the reaction moves towards right hand side. More and more reactants will be converted into products. This will nullify the effect of removal of product.
Which do all cells need in order to function?
oxygen
water
carbon dioxide
offspring
Answer:
oxygen is the correct answer
Explanation:
you need oxygen in order to breath, eat, drink, and many other stuf! hope i helped!
How many moles of titanium are in a sample containing 2.8 x 10^24 atoms?
1) 1.69 x 10^48
2) 4.65 x 10^43
3) 4.65
4) 0.0465
5) 48
Answer:
4.65 moles
Explanation:
To calculate this, we can use Avogradro's Number: 6.022*10^23
[tex]2.8*10^2^4*\frac{1mole}{6.022*10^2^3} =4.65mol[/tex]
So, there are 4.65 moles in 2.8*10^24 atoms of Ti
Which two substances are covalent compounds?
A. C6H12O6(s) and KI(s)
B. C6H1206(s) and HCl(g)
C. KI(S) and NaCl(s)
D. NaCl(s) and HCl(g)
Answer:
Option B is correct: C6H1206(s) and HCl(g)
Determine the number of atoms in 3.14 g gold
14. Explain, in terms of ions, why a 10.0-milliliter sample of 0.10 M NH4Cl(aq) is a poorer conductor of
electricity than a 10.0-milliliter sample of the 0.30 M NH4Cl(aq).
Neeed now
Please please help me
Answer:
I agree with Omar because it depends on what the charge of the object and magnet is. If the magnet is negative and the object is positive, they will pull together. If the magnet is negative and the object is negative then they will pull apart.
Explanation:
Which part of the body transports molecules from food and air to the cells of the body
Answer:
Molecules from food and molecules of oxygen move from the mouth and the nose to cells of the body through a series of blood vessels, including veins, arteries, and microscopically small blood vessels (capillaries), that extend throughout the body.
Explanation: This is right
What is the pH of a 0.08 M solution of Ca(OH),?
Answer:
pH = 12.20
Explanation:
Ca(OH)2 is a strong base, so it dissociates completely. A 0.08 M solution of Ca(OH)2 is 0.16 M OH-, since every mole of Ca(OH)2 has 2 OH-.
Calculate pOH using [OH-] = 0.16 M
pOH = -log(0.16) = 0.80
pH = 14 - pOH = 14 - 0.80 = 12.20
Taking into account the definition of pH and pOH, the pH of a 0.08 M solution of Ca(OH)₂ is 13.21
pHFirst of all, pH is a measure of acidity or alkalinity that indicates the amount of hydrogen ions present in a solution or substance.
The pH is defined as the negative base 10 logarithm of the activity of hydrogen ions, that is, the concentration of hydrogen ions or H₃O⁺:
pH= - log [H⁺]= - log [H₃O⁺]
pOHSimilarly, pOH is a measure of hydroxyl ions in a solution and is expressed as the logarithm of the concentration of OH⁻ ions, with the sign changed:
pOH= - log [OH⁻]
Relationship between pH and pOHThe following relationship can be established between pH and pOH:
pOH + pH= 14
This caseA strong base is one that dissociates completely in water, that is, it contributes the maximum number of OH- ions.
Ca(OH)₂ is a strong base that for each Ca²⁺ cation there are two OH⁻ anions and in which for each mole of Ca(OH)₂ two moles of OH⁻ are formed.
So: [OH⁻]= 2×[Ca(OH)₂]
[OH⁻]= 2×0.08 M
[OH⁻]= 0.16 M
Replacing in the definition of pOH:
pOH= - log (0.16 M)
Solving:
pOH= 0.79
Finally, considering the relationship between pH and pOH:
0.79 + pH= 14
pH= 14 - 0.79
pH= 13.21
In summary, the pH of a 0.08 M solution of Ca(OH)₂ is 13.21
Learn more about pH and pOH:
brainly.com/question/16032912?referrer=searchResults
brainly.com/question/13557815?referrer=searchResults
Fill in the missing information:
1. Complete Nuclear Symbol ________
2. Atomic # ________
3. Mass number ________
# Protons 22
# Electrons 18
# Neutrons 26
4. Charge _________
Answer: 1. Complete Nuclear Symbol : [tex]_{22}^{48}{Ti^{4+}}[/tex]
2. Atomic number : 22
3. Mass number : 48
4. Charge : 4 +
Explanation:
Atomic number is equal to the number of protons.
Mass number is the sum of number of neelectrons. utrons and number of protons.
Given : no of protons = 22 , thus atomic number = 22
Mass number = number of neutrons + number of protons
Mass number = 26 + 22 = 48
Also for a neutral atom , the number of protons is equal to the number of electrons. But here electrons are 4 less than protons, which means the atom has lost 4 electrons and thus will have a charge of 4+.
The atomic number is specific to an element, and the element with atomic number 22 is Titanium (Ti). The representation is [tex]_{22}^{48}{Ti^{4+}}[/tex]
How many grams of solid NaOH are needed to prepare 200. mL of a 5.00% by
volume NaOH solution
A) 8
B) 10
C) 9
D) 7
Answer:
10
Explanation:
Each 100 ml should have 5 solid naom to have 5%,
For 200 ml: 200 *5%=10
The grams of Solid NaOH needed is : ( B ) 10 grams
Volume of solution = 200 mL
Percentage of solid NaOH in solution = 5.0%
Therefore the grams of solid NaOH required to prepare a 200mL solution that contains 5.0% solid will be :
5% * 200 mL
= 10 grams
Hence we can conclude that the grams of solid NaOH needed is 10 grams
Learn more about organic solution : https://brainly.com/question/1163824
HELP!
The law of conservation of energy states:
A. Energy increases exponentially with times
B. Total energy decreases due to energy output.
C. Energy cannot be created or destroyed.
D. Energy always remains in the same form.
Answer:
C
Explanation:
energy cannot be created or destroyed like solar energy for instance. it is already energy because it comes from the sun and for other reason.
Hope this helps!
assign an oxidation number to each element in the following species. H2O
Answer:
the oxidation number of hydrogen is +2, while oxygen is -2
based on their scientific names, you know the cats felis catus and felis bieti do not belong to the same
A. family
B. species
C. zoo
D. domain
In an ecosystem, based on their scientific names, you know the cats felis catus and felis bieti do not belong to the same species.
What is an ecosystem?
Ecosystem is defined as a system which consists of all living organisms and the physical components with which the living beings interact. The abiotic and biotic components are linked to each other through nutrient cycles and flow of energy.
Energy enters the system through the process of photosynthesis .Animals play an important role in transfer of energy as they feed on each other.As a result of this transfer of matter and energy takes place through the system .Living organisms also influence the quantity of biomass present.By decomposition of dead plants and animals by microbes nutrients are released back in to the soil.
Learn more about ecosystem,here:
https://brainly.com/question/1673533
#SPJ2
Litmus is an example of an indicator, a substance that changes color depending on its pH.
a. True
b. False
Calculate the molarity of a MgSO: solution
prepared by adding 0.37 moles of MgSO, to
enough water to make 4.9 L of solution.
Answer in umits of M.
Answer:
is
Explanation:
the explant
Aqueous hydrochloric acid HCl will react with solid sodium hydroxide NaOH to produce aqueous sodium chloride NaCl and liquid water H2O. Suppose 15.7 g of hydrochloric acid is mixed with 27. g of sodium hydroxide. Calculate the maximum mass of sodium chloride that could be produced by the chemical reaction.
Answer:
25.155 gram
Explanation:
HCl(aq.) + NaOH(aq.) ⇒ NaCl + H2O
According the above equation equal number of moles of reactant are producing same number of moles of products.
Now, no. mole of HCl = 15.7/(1+35.5) = 0.43 moles
no. of moles of NaOH = 27/(23+16+1) = 0.675 moles
Since the amount of sodium hydroxide exceeds the amount of hydrochloric acid, the maximum amount of each substance participating in the reaction is HClν ν 0.43 moles .Therefore, the maximum amount of NaCl that can be produced is as follow
= (23+35.5)×0.43 = 25.155 gram
send a pic of the question
A 5.00 g piece of metal is heated to 100.0 C then placed in a beaker containing 20.0 g of water at 10.0 C. The temperature of the water rises to 15.0 C. Calculate the specific heat of the metal
Which of the following is the best way to make a conclusion?
A. The experiment must be manipulated until the results show what you want
B. Estimate results to where they should be
C. Choosing the results you like
D. Comparing data from the experiment to the prediction of the hypothesis
how do I do this I’m confused
by using pro.gram..
[tex]{\huge{\blue{\underline{\underline{ ═══════════}}}}}[/tex]
[tex]{\huge{\pink{\underline{\underline{❑❑❑❑❑❑❑❑❑～}}}}}[/tex]
[tex]{\huge{\orange{\underline{\underline{﹌﹌﹌﹌﹌﹌﹌﹌﹌♪}}}}}[/tex]
[tex]{\huge{\purple{\underline{\underline{✎﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏}}}}}[/tex]
The worst feeling is when you are hurting so badly inside but not a single tear comes out.
Anyone relate?
I know i can.
Answer:
chemistry wow
Explanation:
How many moles of Ag can be obtained from 2.77 moles Cu using the following
balanced reaction?
2AgNO3
+ Cu
Cu(NO3)2
+ 2Ag
Answer:
2.77×2= 5.4 mol Ag can be obtained
how many moles are 20 grams of Helium ?
Answer: The correct answer is 5.00 moles
Explanation: