<span>he density of a material is defined as its mass per
unit volume. In this example, each volume of water is different and
therefore has a specific and unique mass. The mass of water is expressed
in grams (g) or kilograms (kg), and the volume is measured in liters (L), cubic centimeters (cm 3), or milliliters (mL).</span>
According to the periodic table, carbon's molar mass is 12.011 grams per mole (that's the small number under the element). So, just multiply like this to get the answer:

So, there are approximately 0.208 grams in 2.5 moles of carbon.
A reaction in which two ions switch places is called double-displacement reaction.
Explanation:
Double displacement reaction usually takes place between two positive ions or two negative ions. When anions or cations of totally different compounds change places, two totally different compounds are formed.
<u>Syntax for double displacement reaction:
</u>
AB + CD --> AD + BC
It can also be defined in simple terms as the reaction in which exchange of ions takes place is called double displacement reaction.
The chemical reaction is as follows:
NaOH(aq) + HCl(aq) --> NaCl(aq) + H2O (l)
The answer is B "the reaction is exothermic", and C "the reactants lost internal energy."