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3 years ago

A graph of coal reserves in the United States versus time slopes downward.

Chemistry

2 answers:

Dafna1 [17]3 years ago

4 0

Answer:

increased

Explanation:

I believe to be increased ,because the coal is a natural resource to be used.

i really hope it helps

tatyana61 [14]3 years ago

3 0

I remember I had this question before on USA test prep and it’s increased

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When 2.00 kJ of energy is transferred as heat to nitrogen in a cylinder fitted with a piston with an external pressure of 2.00 a

Vilka [71]

Answer: B

Explanation:

6 0

3 years ago

In a titration of 47.41 mL of 0.3764 M ammonia with 0.3838 M aqueous nitric acid, what is the pH of the solution when 47.41 mL +

Volgvan

Answer: The pH of the solution is 1.136

Explanation:

To calculate the moles from molarity, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}$

For ammonia:

Molarity of ammonia = 0.3764 M

Volume of ammonia = 47.41 mL = 0.04741 L (Conversion factor: 1 L = 1000 mL)

Putting values in above equation, we get:

$0.3764mol/L=\frac{\text{Moles of ammonia}}{0.04741L}\\\\\text{Moles of ammonia}=0.01784mol$

For nitric acid:

Molarity of nitric acid = 0.3838 M

Volume of ammonia = (47.41 + 10.00) mL = 57.41 mL= 0.05741 L

Putting values in above equation, we get:

$0.3838mol/L=\frac{\text{Moles of nitric acid}}{0.05741L}\\\\\text{Moles of nitric acid}=0.02203mol$

After the completion of reaction, amount of nitric acid remained = 0.022 - 0.0178 = 0.0042 mol

For the reaction of ammonia with nitric acid, the equation follows:

$NH_3+HNO_3\rightarrow NH_4NO_3$

At $t=0$ 0.0178 0.022

Completion 0 0.0042 0.0178

As, the solution of the reaction is made from strong acid which is nitric acid and the conjugate acid of weak base which is ammonia. So, the pH of the reaction will be based totally on the concentration of nitric acid.

To calculate the pH of the reaction, we use the equation:

$pH=-\log[H^+]$

where,

$[H^+]=\frac{0.0042mol}{0.05741L}=0.0731M$

Putting values in above equation, we get:

$pH=-\log(0.0731)\\\\pH=1.136$

Hence, the pH of the solution is 1.136

8 0

3 years ago

What can you conclude about these two reactions based on the chemical equations? Reaction A: 6CO2(g) + 6H2O(l) + sunlight ? C6H1

OlgaM077 [116]

Given reactions:

(A) 6CO2(g) + 6H2O(l) + sunlight → C6H12O6(aq) + 6O2(g)

(B) 2H2(g) + O2(g) → 2H2O(g) + energy

Exothermic reactions are those which proceed with the release of heat/energy. In contrast, endothermic reactions proceed with the absorption of energy in the form of heat or light.

Since reaction A required sunlight, it is endothermic. Reaction B releases energy, hence exothermic

Ans: (B)

A is endothermic

B is exothermic

8 0

3 years ago

1.Oxygen (O) is a gas found in the 16th column of the periodic table. What statement is true about oxygen and the other elements

Lady_Fox [76]

1. A. All the elements in the column have similar chemical properties.

2. Substances on the periodic table cannot be broken down into other substances and are therefore elements.

6 0

3 years ago