Steps Of Balancing Equations Quiz

1. A ssa A substance that undergoes a change in a chemical reaction is

A product

A chemical

A reactant

An enzyme

A reactant (left to the --->)is the substance that undergoes changes.

Explanation

A reactant (left to the --->)is the substance that undergoes changes.

2. What happens in a chemical reaction?

Atoms are destroyed

Atoms are created

Atoms are rearranged

Atoms are heated or cooled

Remember the Law of Conservation of matter: Matter cannot be created nor destroyed, although it may be rearranged.

Explanation

Remember the Law of Conservation of matter: Matter cannot be created nor destroyed, although it may be rearranged.

3. A chemical equation is balanced by changing or adding

Chemical symbols

Subscripts

Coefficients

Reactants

The coefficients (number in front of atoms or molecules)are the only item that can be changed when balancing chemical equations.

Explanation

The coefficients (number in front of atoms or molecules)are the only item that can be changed when balancing chemical equations.

4. What coefficients will satisfy the following equation
Hg + O₂ ----> HgO

1,1,1

2,2,1

2,1,2

1,2,2

In the reactants side, I have 1 mercury atom and 2 Oxygen atoms, so I need to have the same in the products side, a number 2 in front of HgO will give 2 Oxygen, but also gives me 2 Hg, so now I need to add a 2 in front of my Hg in the reactant side to have 2,1,2

Explanation

In the reactants side, I have 1 mercury atom and 2 Oxygen atoms, so I need to have the same in the products side, a number 2 in front of HgO will give 2 Oxygen, but also gives me 2 Hg, so now I need to add a 2 in front of my Hg in the reactant side to have 2,1,2

5. What coefficients will satisfy the following equation
AgNO₃ + NaCl ----> AgCl + NaNO₃

2,2,2,1

1,1,1,1

1,2,1,2

2,1,2,1

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Explanation

Are you loving it?

6. A balanced chemical equation shows the proportions of reactants and products necessary for

The reaction to occur

Mass to be conserved.

Energy use to be minimized.

Electrolysis to occur.

When we balance an equation we know how much reactants we need for the reaction to occur. It the same as writing a recipe (one cup of rice needs two cups of water, try it!).

Explanation

When we balance an equation we know how much reactants we need for the reaction to occur. It the same as writing a recipe (one cup of rice needs two cups of water, try it!).

7. What coefficients will satisfy the following equation
Al + O₂ --> Al₂O₃

1,3,2

4,3,2

2,2,2

2,1,3

To balance the equation Al + O2 -> Al2O3, we need to ensure that the number of atoms of each element is the same on both sides of the equation. In this case, we have 1 Al atom on the left side and 2 Al atoms on the right side, so we need to multiply the coefficient of Al by 2. Similarly, we have 2 O atoms on the left side and 3 O atoms on the right side, so we need to multiply the coefficient of O2 by 3. Therefore, the coefficients that satisfy the equation are 4, 3, 2.

Explanation

To balance the equation Al + O2 -> Al2O3, we need to ensure that the number of atoms of each element is the same on both sides of the equation. In this case, we have 1 Al atom on the left side and 2 Al atoms on the right side, so we need to multiply the coefficient of Al by 2. Similarly, we have 2 O atoms on the left side and 3 O atoms on the right side, so we need to multiply the coefficient of O2 by 3. Therefore, the coefficients that satisfy the equation are 4, 3, 2.

8. What coefficients will satisfy the following equation
H₂ + O₂ ---> H₂O

2,2,1

2,1,2

4,1,2

2,2,2

The equation represents the reaction between hydrogen gas (H2) and oxygen gas (O2) to form water (H2O). The coefficients in front of each compound indicate the number of molecules involved in the reaction. In this case, the equation is balanced when there are 2 molecules of hydrogen gas, 1 molecule of oxygen gas, and 2 molecules of water. This ensures that the number of atoms on both sides of the equation is equal, satisfying the law of conservation of mass.

Explanation

The equation represents the reaction between hydrogen gas (H2) and oxygen gas (O2) to form water (H2O). The coefficients in front of each compound indicate the number of molecules involved in the reaction. In this case, the equation is balanced when there are 2 molecules of hydrogen gas, 1 molecule of oxygen gas, and 2 molecules of water. This ensures that the number of atoms on both sides of the equation is equal, satisfying the law of conservation of mass.

9. If you start with 5 mol of O₂ in the reaction 2Mg + O₂ ----> 2MgO, how many moles of Mg will you need?

4

5

8

10

Based on the balanced equation, one mol of Oxygen reacts with 2 mol of Magnesium, therefore if I multiply one mol five times I need to multiply the two moles of Mg five times too (2 X 5 = 10)

Explanation

Based on the balanced equation, one mol of Oxygen reacts with 2 mol of Magnesium, therefore if I multiply one mol five times I need to multiply the two moles of Mg five times too (2 X 5 = 10)