Any substance composed of two or more elements that are chemically combined in a fixed proportion is

Enter an equation showing how this buffer neutralizes added aqueous acid (HI). Express your answer as a chemical equation. Ident

andrey2020 [161]

Answer:

$H^++NH_3\rightleftharpoons NH_4^+$

Explanation:

Hello there!

In this case, since the buffer is not given, we assume it is based off ammonia, it means the ammonia-ammonium buffer, whereas the ammonia is the weak base and the ammonium ion stands for the conjugate acid. In such a way, when adding HI to the solution, the base of the buffer, NH3, reacts with the former to promote the following chemical reaction:

$H^++NH_3\rightleftharpoons NH_4^+$

Because the HI is totally ionized in solution so the iodide ion becomes an spectator one.

Best regards!

5 0

2 years ago

In molecules, energy is stored in? Atoms Electrons The Nucleus Bonds

Nikolay [14]

Answer:

Atoms

Explanation:

Energy, potential energy, is stored in the covalent bonds holding atoms together in the form of molecules. This is often called chemical energy.

4 0

2 years ago

If a system performs 147 kJ of work while receiving 47 kJ of heat, what is change in its internal energy?

Verdich [7]

Answer:

-100 kJ

Explanation:

We can solve this problem by applying the first law of thermodynamics, which states that:

$\Delta U = Q-W$

where:

$\Delta U$ is the change in internal energy of a system

Q is the heat absorbed/released by the system (it is positive if absorbed by the system, negative if released by the system)

W is the work done by the system (it is positive if done by the system, negative if done on the system)

For the system in this problem we have:

W = +147 kJ is the work done by the system

Q = +47 kJ is the heat absorbed by the system

So , its change in internal energy is:

$\Delta U = +47 - (+147) =-100 kJ$

6 0

2 years ago

Zn + 2 HCl --> ZnCl2 + H2 How many moles of hydrochloric acid (HCl) are used (assume a complete reaction) if 8.3 moles of zin

uysha [10]

Answer:

E. 16.6 mol HCl

Explanation:

The equation for the reaction is;

Zn + 2 HCl --> ZnCl2 + H2

From the reaction 2 moles of HCl produces 1 mole of ZnCl2

Therefore; 8.3 moles of ZnCl2 will be produced by;

= 8.3 moles ×2

= 16.6 Moles of HCl

Therefore; E. 16.6 mol HCl

4 0

3 years ago

Ethylene produced by fermentation has a specific gravity of 0.787 at 25 degree Celsius. What is the volume of 125g of ethanol at

WITCHER [35]

Answer: The volume of given amount of ethanol at this temperature is 159.44 mL

Explanation:

Specific gravity is given by the formula:

$\text{Specific gravity}=\frac{\text{Density of a substance}}{\text{Density of water}}$

We are given:

Density of water = 0.997 g/mL

Specific gravity of ethanol = 0.787

Putting values in above equation, we get:

$0.787=\frac{\text{Density of a substance}}{0.997g/mL}\\\\\text{Density of a substance}=(0.787\times 0.997g/mL)=0.784g/mL$

Density is defined as the ratio of mass and volume of a substance.

$\text{Density}=\frac{\text{Mass}}{\text{Volume}}$ ......(1)

Given values:

Mass of ethanol = 125 g

Density of ethanol = 0.784 g/mL

Putting values in equation 1, we get:

$\text{Volume of ethanol}=\frac{125g}{0.784g/mL}=159.44mL$

Hence, the volume of given amount of ethanol at this temperature is 159.44 mL

6 0

2 years ago