Answer:The world population increased from 1 billion in 1800 to 7.7 billion today. The world population growth rate declined from 2.2% per year 50 years ago to 1.05% per year. Other relevant research: World population growth – This article is focusing on the history of population growth up to the present.
Explanation:
A 10 M concentrated stock solution of NaCl is used to prepare 2 liters of diluted 1 M
solution. Which of the following is true for the process used to achieve the required
dilution? (5 points)
O The volume of the solvent used is less than 0.1 liters.
O The volume of stock solution used is less than 0.1 liters.
The volume of stock solution used is more than 2 liters.
The volume of the solvent used is less than 2 liters.
Answer: It is true for the process used to achieve the required dilution that volume of the solvent used is less than 2 liters.
Explanation:
Given: [tex]M_{1}[/tex] = 10 M, [tex]V_{1}[/tex] = ?
[tex]M_{2}[/tex] = 1 M, [tex]V_{2}[/tex] = 2 L
The volume of stock solution is calculated as follows.
[tex]M_{1}V_{1} = M_{2}V_{2}\\10 M \times V_{1} = 1 M \times 2\\V_{1} = 0.2 L[/tex]
A solution which contains small amount of solute is called a dilute solution. Whereas a solution which contains more amount of solute is called a concentrated solution.
The stock solution is used for dilution and hence, it acts as a solvent. Its calculated volume is 0.2 L.
This means that volume of the solvent used is less than 2 liters.
Thus, we can conclude that it is true for the process used to achieve the required dilution that volume of the solvent used is less than 2 liters.
Answer: The volume of the solvent used is less than 2 liters.
Explanation:
Names for following compounds.
a)CO²
b)NaCI
c)S²CI²
d)NaF
Are plants and animal pH sensitive?
Answer:
Plants and animals are pH sensitive. The growth of plants is dependent on the nature of the soil. If the pH of the soil is greater than 7 and is alkaline, then the plants cannot grow in the soil.
Explanation:
Which elements are the transuranium elements? Use the periodic table link from the tools bar to answer the question.
those with atomic numbers from 93 to 118
those with atomic numbers 2, 10, 18, 36, 54, and 86
those with atomic numbers 3, 11, 19, 37, 55, and 87
those with atomic numbers from 89 to 103
Answer:
(A) those with atomic numbers from 93 to 118
Explanation:
got the answer from q**zlet. hope this helps :)
An investigation is conducted into how the mass of magnesium metal reacting with hydrochloric acid affects the amount of hydrogen gas produced.
Masses of 0.10g, 0.20g, 0.30g and 0.40g of powdered Mg metal are reacted with hydrochloric acid(HCl). The conical flask containing the reaction mixture of Mg and HCl is connected to another conical flask with a hose. The hydrogen gas produced by the reaction is collected in this conical flask. The greater the amount of hydrogen gas produced by the reaction the greater the pressure of the gas in the flask.
Answer:
A) what is the independent variable:
B) what is the dependent variable:
C) write a hypothesis for this investigation:
D) give 2 variables that should have been controlled for this investigation:
An investigation is conducted into how the mass of magnesium metal reacting with hydrochloric acid affects the amount of hydrogen gas produced.
Masses of 0.10g, 0.20g, 0.30g and 0.40g of powdered Mg metal are reacted with hydrochloric acid(HCl). The conical flask containing the reaction mixture of Mg and HCl is connected to another conical flask with a hose. The hydrogen gas produced by the reaction is collected in this conical flask. The greater the amount of hydrogen gas produced by the reaction the greater the pressure of the gas in the flask.
Answer:
A) what is the independent variable:
B) what is the dependent variable:
C) write a hypothesis for this investigation:
D) give 2 variables that should have been controlled for this investigation:
In the equation C H4 + O2 C O2 + H2 O, what are the reactants?
O2--> C O2
C O2 + H2 O
C H4 + H2 O
C H4 + O2
Answer:
Explanation:
A gas is contained in a horizontal cylinder with a moveable piston of cross-sectional area 0.33\text{ m}^20.33 m 2 . The region outside the cylinder is at standard ambient temperature and pressure, 298\text{ K}298 K and 1\text{ bar}1 bar. When 2040\text{ J}2040 J of heat flow into the gas, the internal energy of the gas increases by 1380\text{ J}1380 J. Calculate the distance through which the piston moves. You may assume friction is negligible.
Answer:
0.02 m
Explanation:
∆U = q + w
w = ∆U - q = (1380 - 2040) J = -660 J
w = -p∆V = -pA∆h
∆h = -w/(pA)
p = 1 bar × (100000 Pa/1 bar) = 100000 Pa
∆h = -(-660 J)/(100000 Pa×0.33 m²) = 0.02 m
A gas is contained in a horizontal cylinder with a moveable piston of cross-sectional area 0.33\text{ m}^20.33 m 2. The distance through which the piston moves is 0.02 m.
What is piston ?Among other related systems, pistons are found in reciprocating engines, reciprocating pumps, gas compressors, hydraulic cylinders, and pneumatic cylinders. It is the moving part that is enclosed in a cylinder and sealed off from the gas by piston rings.
The piston, which is a part of combustion engines, transforms the energy released during combustion into a mechanical action and sends it, via the piston pin and connecting rod, to the crankshaft as a torsional force. The piston in the cylinder goes up and down when the engine is running.
The equation given by
∆ U = q + w
w = ∆ U - q
= ( 1380 - 2040 )
J = -660 J
w = -p∆V
= -pA∆h
∆h = -w / (pA)
p = 1 bar × ( 100000 Pa / 1 bar )
= 100000 Pa
∆h = - ( -660 J) / ( 100000 Pa × 0.33 m² )
= 0.02 m
Thus, The distance through which the piston moves is 0.02 m.
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the cells are utilising _______ which are produced during the process of cell respiration
Answer:
sana nakatulong po sainyo
PLEASE HELP
Which chemical reaction supports the Law of Conservation of Mass?
Answer:A
Explanation:
Add more drink mix until you notice a color change. Have you increased or decreased the concentration? (Higher number means a higher concentration).
Answer:
Increased the concentration
Explanation:
Complete Question
Open the simulation by pushing the play button. Begin by dragging the concentration tester overto the liquid and add drink mix until the concentration reaches approximately 2.oo mol/L. This means there are 2.00 moles of the drink mix in 1 Liter of the solution. Add more drink mix until you notice a color change. Have you increased or decreased the concentration? (Higher number means a higher concentration).
Solution
Drink mix is basically the solute which is added to solvent i.e water.
The higher is the amount of drink mix in the solvent, the higher is the concentration of the solute and hence darker is the color of the drink.
Hence, in the case the concentration of the drink has been increased.
5.(08.02 MC)
A 0.680 M Ca(OH)2 solution was prepared by dissolving 55.0 grams of Ca(OH)2 in enough water. What is the total volume of the solution formed? (4 points)
O 1.09 liters
0 1.23 liters
2.01 liters
O 2.18 liters
Answer: 1.09 Liers
Explanation:
I did the problem and got it correct.
Answer:
A. 1.09
Explanation:
I did the Chemistry Exam
Sodium chloride is produced from its elements through a synthesis reaction. What mass of each reactant would be required to produce 22.0 mol of sodium chloride? sodium
Answer:
506.0 g sodium and 778.8 g chlorine gas
Explanation:
The elements from which sodium chloride (NaCl) is composed are sodium (Na) and chlorine (Cl). Thus, the chemical equation for the production of sodium chloride (NaCl) from sodium (Na) and chlorine gas (Cl₂) is the following:
2Na(s) + Cl₂(g) → 2NaCl(s)
According to the balanced equation, 2 moles of NaCl are produced from 2 moles of Na(s) and 1 mol of Cl₂. To produce 22.0 mol of NaCl, we need:
22.0 mol NaCl x 2 mol Na(s)/2 mol NaCl = 22.0 mol Na(s)
22.0 mol NaCl x 1 mol Cl₂/2 mol NaCl = 11.0 mol Cl₂
Now, we convert the moles of each reactant to grams with the molar mass (MM) of the compound:
MM(Na) = 23 g/mol
22.0 mol Na x 23 g/mol = 506.0 g Na(s)
MM(Cl₂) = 35.4 g/mol x 2 = 70.8 g/mol
11.0 mol Cl₂ x 70.8 g/mol = 778.8 g Cl₂
Therefore, it is required a mass of 506.0 grams of Na(s) and a mass of 778.8 grams of Cl₂ to produce 22.0 mol of NaCl.
If you have 2 water molecules together, would you expect them to sit "hydrogen by hydrogen" or "hydrogen to oxygen"? Why?
Answer:
"hydrogen to oxygen"
Explanation:
Hydrogen bonds are formed when hydrogen is bonded to highly electronegative element such as Chlorine, fluorine, oxygen etc.
In hydrogen bonding, the hydrogen atom of one molecule of water is attracted to the oxygen atom of another molecule of water via permanent dipole-dipole interaction.
Hence, If you have 2 water molecules together, they always sit "hydrogen to oxygen" as a result of dipole - dipole interaction and hydrogen bonding between water molecules.
How to avoid the process of corrosion?
No Links please.
I needASAP!
Answer:
5 Different Types of Corrosion Prevention Methods
Barrier Coatings. One of the easiest and cheapest ways to prevent corrosion is to use barrier coatings like paint, plastic, or powder. ...
Hot-Dip Galvanization. ...
Alloyed Steel (Stainless) ...
Cathodic Protection. ...
EonCoat.
HELP!
The piston of an internal combustion engine
compresses 218 mL of gas. The final pressure
is 15 times greater than the initial pressure.
What is the final volume of the gas, assuming
constant temperature?
Answer in units of mL.
Answer:
14.53
Explanation:
V1= 218ML
V2= ?
P2= 15P1
USING BOYLE'S LAW
P1V1= P2V2
V2= P1V1/P2
V2 = P1(218ML)/15P1 = 14.53ML
Convert 7.65 x 10^5 mL into Mega-Liter.
Answer:
[tex]1 \: ml = \frac{1}{1000} l \\ 7.65 \times {10}^{5} \: ml = \frac{7.65 \times {10}^{5} }{1000} \\ = 765 \: l[/tex]
Where and why the U.S. acid rain damage is the greatest.
Answer:
Some acid rain occurs naturally, but sulfur dioxide and nitrogen oxide emissions from smokestacks combine with rain to make sulfuric and nitric acid in amounts that harm.
Explanation:
which term is defined as a measure of the average kinetic energy of the particles in a sample
Where is glycogen stored? (choose all that apply)
muscles
bones
organs
skin
What is the possible results of the test of a few drops of a mixture of sodium hydroxide and copper(ii) tetraoxosulphate (vi) solution added to a sample of urine test in a test tube
Answer:
The urine may turn purple or remain colourless
Explanation:
Adding sodium hydroxide (NaOH) and hydrated copper(II) sulfate to urine in a test tube is a test for proteins in urine.
This test depends on the ability of sodium hydroxide (NaOH) and hydrated copper(II) sulfate to form purple-coloured cordination complexes with peptides. The appearance of this purple colour is a positive test for protiens in urine.
Hence, when a few drops of a mixture of sodium hydroxide and copper(ii) tetraoxosulphate (vi) solution added to a sample of urine test in a test tube, the solution may turn purple indicating the presence of proteins in urine or remain colourless indicating the absence of proteins in urine.
True or false intrusive igneous rock will never be found on Earth's surface?
Answer:
false
Explanation:
Answer:
false
Explanation:
lava is on the earth
What are proteins made up of?
Answer:
cereal egg fish
that's a ll I know
Giving Brainliest and 20 points to best answer with explanation.
What is the relationship between surface tension and Cohesion?
A. As cohesion increases, surface tension increases
B. As cohesion increased, surface tension decreases.
Answer:
A
Explanation:
Cohesion is basically the attraction of same molecules and surface tension occurs due to the attraction of molecules . Therefore as cohesion becomes high, surface tension becomes here. We can say then that Cohesion is directly proportional to surface tension
The energy in biomass is used to make electricity. How is the energy stored in
biomass?
A. In chemical bonds
B. In the nucleus
C. As kinetic energy
D. As light energy
Answer:
In chemical bonds
Explanation:
A P E X
The energy in biomass is used to make electricity. The energy stored in
biomass in the form of chemical bonds.
What is biomass?Biomass was organic, which means it must be made up of material derived from living beings like plants as well as animals.
What is chemical bonds?
A chemical bond can be known as a long-term interaction involving atoms, ions, as well as molecules which allows chemical compounds to occur.
Biomass is made up of chemical energy that has been stored from the sun. Process called photosynthesis by which plants make biomass. Biomass can also be produced by burning for heat or processed into renewable liquid as well as gaseous fuels using a variety of techniques.
Therefore, the correct answer will be option A.
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Balance the following equation: _H2+ __02 - __ H20
Answer:
2
H
2
+
O
2
=
2
H
2
O
Explanation:
From the original equation, you first need to write each component separately.
H
2
+
O
2
=
H
2
O
Left side: H = 2 ; O = 2 (number based on the subscript)
Right side: H = 2 ; O = 1 (number based on the subscripts; no subscript means that the element is just 1)
Notice that the number of H is already balance but the number of O is not. In order to balance the O, you need to multiply the element by 2, but you CANNOT do this by simply changing the subscript.
Hence,
H
2
+
O
2
=
2
H
2
O
Left side: H = 2 ; O = 2
Right side: H = 2 x 2 = 4 ; O = 1 x 2 = 2
Now, notice that the number of O is now balance (both are 2) but the number of H is not (since
H
2
O
is a substance and not an element, you need to multiply everything by 2). So, what to do?
You also multiply the left side H by 2. Hence,
2
H
2
+
O
2
=
2
H
2
O
Left side: H = 2 x 2 = 4 ; O = 2
Right side: H = 2 x 2 = 4 ; O = 1 x 2 = 2
The equation is now balanced.
Please help me ASAP State 2 uses of a retort
stand according to Chemistry
Answer:
2 uses of retort stand:
Retorts are used for distillation experiments (such as organic distillations) and titrations (where they hold a burette). They are also used as supports in filtration.What does an increase in temperature do to the reaction rate?
Answer:
An increase in temperature typically increases the rate of reaction because an increase in temperature will raise the average kinetic energy of the reactant molecules. Therefore, a greater proportion of molecules will have the minimum energy necessary for an effective collision.Increasing the temperature increases reaction rates because of the disproportionately large increase in the number of high energy collisions. It is only these collisions (possessing at least the activation energy for the reaction) which result in a reaction.
Explanation:
Can you please give this answer a brainliest answer please
Balance this equation
If i had 6 mol Cl2, how many mol FeCl3 would be made in:
2Fe+3Cl2-->2FeCl3
Answer:
4 mol FeCl3
Explanation:
[tex]6molCl_{2} *\frac{2mol FeCl_3}{3molCl_2}[/tex] = 4 mol FeCl3
Use the train-track method shown up above. We are simply setting up molar ratios derived from balanced equation to solve this.
Choose the options below that are true of standard reduction potential. (select all that apply) Select all that apply: All standard reduction potentials are measured against that of the reduction of hydrogen ions to H2 gas. The standard reduction potential of a cell is determined by subtracting the standard reduction for the reaction at the anode from the standard reduction potential for the reaction at the cathode. Standard reduction potentials are dependent on reaction stoichiometry. The standard reduction potential for a cell is determined by adding the standard reduction potential for the reaction at the anode to the standard reduction potential for the reaction at the cathode.
Answer:
All standard reduction potentials are measured against that of the reduction of hydrogen ions to H2 gas.
Explanation:
The standard hydrogen electrode (SHE) serves as a sort of reference electrode. All standard electrode potentials of chemical systems are measured against the standard hydrogen electrode whose electrode potential has been arbitrarily set at 0.00 V.
The reduction potential of any other system is measured against the standard hydrogen electrode by connecting that half cell to the standard hydrogen electrode and observing the reading of the voltmeter. The standard hydrogen electrode consists of hydrogen ions of unit activity, hydrogen gas at 1 atm and the system is maintained at a temperature of 298 K.
Standard reduction potentials are measured against that of the reduction of hydrogen ions to [tex]H_2[/tex] gas because hydrogen is chosen as a standard reference and has electrode potential zero.
It is impossible to measure absolute electrode potential for an electrode without forming cell . Therefore it is assumed that standard electrode potential for hydrogen is zero
The standard reduction potential of a cell is determined by subtracting the standard reduction for the reaction at the anode from the standard reduction potential for the reaction at the cathode.
[tex]E_c_e_l_l[/tex]°[tex]= E_c_a_t_h_o_d_e[/tex]°[tex]- E_a_n_o_d_e[/tex]°
The species liking to get reduced is defined in term of standard reduction potential.
The species whose standard reduction potential is to be calculated is placed at cathode and at anode hydrogen electrode is used.
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