Question

1. label the parts of a chemical reaction. you can also check out this youtube video. 3. list the reactants and products of photosynthesis.

Explanation:

Step1: Identify reactants

In a chemical reaction, reactants are on the left - hand side of the arrow. Here, the reactants are magnesium ($Mg$) and oxygen ($O_2$). So, D: Reactants, which are $2Mg$ and $O_2$.

Step2: Identify the arrow

The arrow in a chemical reaction shows the direction of the reaction. So, B: Reaction arrow.

Step3: Identify products

Products are on the right - hand side of the arrow. Here, the product is magnesium oxide ($MgO$). So, E: Products, which is $2MgO$.

Step4: Identify coefficients

Coefficients are the numbers in front of the chemical formulas. So, A: Coefficient of $Mg$ (which is 2), C: Coefficient of $MgO$ (which is 2).

Answer:

A: Coefficient of $Mg$ (2)
B: Reaction arrow
C: Coefficient of $MgO$ (2)
D: Reactants ($2Mg$ and $O_2$)
E: Products ($2MgO$)