Question

Balance the chemical equation: ___ Na + ___ MgF2 → ___ NaF + ___ Mg

a) Na=1, Mg=1, F=2
b) Na=2, Mg=1, F=2
c) Na=2, Mg=2, F=2
d) Na=1, Mg=2, F=2
Type of reaction: ________________

Balance the chemical equation: ___ Mg + ___ HCl → ___ MgCl2 + ___ H2
a) Mg=1, H=2, Cl=2
b) Mg=1, H=1, Cl=2
c) Mg=2, H=2, Cl=1
d) Mg=1, H=2, Cl=1
Type of reaction: ________________

Balance the chemical equation: ___ Cl2 + ___ KI → ___ KCl + ___ I2
a) Cl=2, K=2, I=2
b) Cl=1, K=2, I=2
c) Cl=1, K=1, I=2
d) Cl=2, K=1, I=1
Type of reaction: ________________

Balance the chemical equation: ___ NaCl → ___ Na + ___ Cl2
a) Na=1, Cl=1
b) Na=2, Cl=2
c) Na=1, Cl=2
d) Na=2, Cl=1
Type of reaction: ________________

Balance the chemical equation: ___ Na + ___ O2 → ___ Na2O
a) Na=4, O=1
b) Na=2, O=1
c) Na=1, O=2
d) Na=2, O=2
Type of reaction: ________________

Balance the chemical equation: ___ Nap + ___ HCl → ___ H2 + ___ NaCl
a) Na=2, H=2, Cl=2
b) Na=1, H=2, Cl=1
c) Na=2, H=1, Cl=2
d) Na=1, H=1, Cl=1
Type of reaction: ________________

Balance the chemical equation: ___ K + ___ Cl2 → ___ KCl
a) K=2, Cl=1
b) K=1, Cl=2
c) K=1, Cl=1
d) K=2, Cl=2
Type of reaction: ________________

Balance the chemical equation: ___ C2H6 + ___ O2 → ___ CO2 + ___ H2O
a) C=2, H=6, O=7
b) C=2, H=6, O=5
c) C=1, H=3, O=4
d) C=3, H=8, O=4
Type of reaction: ________________

Balance the chemical equation: ___ Na2S + ___ HCl → ___ NaCl + ___ H2S
a) Na=2, S=1, H=2, Cl=2
b) Na=1, S=2, H=2, Cl=2
c) Na=2, S=2, H=1, Cl=1
d) Na=1, S=1, H=2, Cl=1
Type of reaction: ________________

Balance the chemical equation: ___ Ca + ___ O2 → ___ CaO
a) Ca=1, O=1
b) Ca=1, O=2
c) Ca=2, O=1
d) Ca=2, O=2
Type of reaction: ________________

Answer 1

Chemical equations must be balanced to reflect the conservation of mass, and coefficients are adjusted to ensure that each element has the same number of atoms on both sides of the equation. Examples include reactions of magnesium with hydrochloric acid, chlorine with potassium iodide, and the decomposition of sodium chloride.

Step-by-step explanation:

To answer these questions correctly, we need to apply the law of conservation of mass, which tells us that atoms cannot be created or destroyed in a chemical reaction. Therefore, each side of a chemical equation must have the same number of atoms of each element. In balancing chemical equations, we adjust coefficients (the numbers in front of compounds) to achieve this balance.

Here are some correctly balanced equations based on the given options:

1. The equation for magnesium reacting with hydrochloric acid to produce magnesium chloride and hydrogen gas is: Mg + 2HCl → MgCl₂ + H₂. This is a single displacement reaction.
2. The balanced equation for chlorine reacting with potassium iodide to produce potassium chloride and iodine is: Cl₂ + 2KI → 2KCl + I₂. This is a halogen displacement reaction.
3. The balanced equation for sodium chloride decomposing into sodium and chlorine gas is: 2NaCl → 2Na + Cl₂. This is a decomposition reaction.