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3 years ago

Which is one way to determine whether a reaction was a chemical reaction or a nuclear reaction?

Chemistry

2 answers:

Elena-2011 [213]3 years ago

7 0

Answer:

A. Check for a change in total mass during the reaction.

Roman55 [17]3 years ago

5 0

Answer: check for a change in total mass during a reaction.

According to the law of conservation of mass during a chemical change the total mass of the products remains equal to the total mass of the reactants: there is not change in the total mass.

During nuclear reactions the mass can change due to the huge release of energy which proceeds from mass change, as per the famous equation ΔE =Δm. c^2.

You might be interested in

Calcium carbonate decomposes at high temperatures to give calcium oxide and carbon

Dafna1 [17]

Answer:

Explanation:

Calcium carbonate decomposes at high temperatures to give calcium oxide and carbon

dioxide as shown below.

CaCO3(s) = CaO(s) + CO2(g)

The Kp for this reaction is 1.16 at 800°C. A 5.00 L vessel containing 10.0 g of CaCO3(s)

was evacuated to remove the air, sealed, and then heated to 800°C. Ignoring the volume

occupied by the solid, what will overall mass percent of carbon in the solid once equilibrium is reached?

4 0

2 years ago

Sics and Chemistry HHSA

Ivan

Answer:

0 They have no freedom to move

Explanation:

The movement of atoms in a solid state of matter are confined to vibrations on a molecular level so the atoms do not have freedom to move

answer one describes atomic movement in a gas state

answer two describes atomic movement in a liquid state

7 0

4 years ago

Rewrite each of the following equations for phase changes, to include the heat required for the phase change. Use values from la

nika2105 [10]

Answer:

The complete equation (a) is:

$H_2O_{(l)}->H_2O_{(l)}+333.55 J/g$ , and is an exothermica phase change

The complete equation (b) is:

$H_2O_{(l)}+2257J/g->H_2O_{(g)}$ , and is an endothermic phase change.

Explanation:

<em>Equation (a):</em>

$H_2O_{(l)}->H_2O_{(l)}+333.55 J/g$ , is showing a phase change from a more-energetic state (liquid) to a relative-less-energetic state (solid), that means, that in order to have the phase change, it is requiered to remove heat (energy) from the water, this is known an exothermic (releases heat).

<em>Equation (b).</em>

$H_2O_{(l)}+2257J/g->H_2O_{(g)}$ , shows that to change from a relative-less-energetic phase (liquid) to a more-energetic one (gas), it would be needed to supply energy in order to acomplish this. And it is called endothermic (absorves heat)

5 0

4 years ago

Starting with 0.657 g of lead(II) nitrate, a student collects 0.925 g of precipitate. If the calculated mass of precipitate is 0

tatuchka [14]

Answer:

101.2%

Explanation:

Given:

Theoretical yield of the precipitate = 0.914 g

Actual yield of the precipitate = 0.925 g

Now, the percent yield is given as a ratio of actual yield by theoretical yield expressed as a percentage.

Framing in equation form, we have:

$\%\ yield=\frac{Actual\ yield}{Theoretical\ yield}\times 100$

Now, plug in 0.925 g for actual yield, 0.914 g for theoretical yield and solve for % yield. This gives,

$\%\ yield=\frac{0.925\ g}{0.914\ g}\times 100\\\\\%\ yield=1.012\times 100\\\\\%\ yield=101.2\%$

Therefore, the percent yield is 101.2%.

5 0

4 years ago

If air contains 78% Nitrogen by volume, what is the solubility of nitrogen in water at 25 degree celisus

Svet_ta [14]

The solubility of nitrogen in water at 25 °C= 4.88 x 10⁻⁴ mol/L

<h3>Further explanation</h3>

Given

78% Nitrogen by volume

Required

The solubility of nitrogen in water

Solution

Henry's Law states that the solubility of a gas is proportional to its partial pressure

Can be formulated

S = kH. P.

S = gas solubility, mol / L

kH = Henry constant, mol / L.atm

P = partial gas pressure

In the standard 25 C state, the air pressure is considered to be 1 atm, so the partial pressure of N₂ -nitrogen becomes:

Vn / Vtot = Pn / Ptot

78/100 = Pn / 1

Pn = 0.78 atm

Henry constant for N₂ at 25 °c = 1600 atm/mol.L=6.25.10⁻⁴ mol/L.atm

The solubility :

$\tt S=6.25.10^{-4}\times 0.78\\\\S=4.88\times 10^{-4}~mol/L$

7 0

3 years ago