Answer:
To balance an equation such as Mg + O2 → MgO, the number of the atoms in the product must equal the number of the atoms in the reactant. Mg + O2 --> MgO. To balance an equation, we CAN change coefficients, but NOT SUBSCRIPTS to balance equations.
Explanation:
Answer:

Explanation:
<u>Density
</u>
The density of a substance is the mass per unit volume. The density varies with temperature and pressure.
The formula to calculate the density of a substance of mass (m) and volume (V) is:

The cube has a mass of m=3.75 g and a volume of V=3 ml, thus the density is:


Since 1 kg=1000 mg and 1 lt = 1000 ml, the density has the same value but with different units:

Id say d because it releases hydrogen and on the other hand a base receives it
<span />