<span>Displaced volume :
final volume - initial volume
32.4 mL - 25.2 mL => 7.2 mL
Density = mass / volume
D = 22.6 g / 7.2 mL
D = 3.1388 g/mL
hope this helps!</span>
Answer:
CH4 - Methane
B2Si - Diboron monosilicide
N2O5 - Dinitrogen pentoxide
CO2 - Carbon dioxide
Explanation:
When it comes to naming covalent compounds, there are several rules.
The name is derived based on the formula. For example, N2O5. The first element is nitrogen. To the name of the element, you add the prefix that tells us how many of its atoms are in the compound. In this case, there are two atoms, which means that the prefix will be <em>di</em>- (dinitrogen). The second element is oxygen. You are supposed to take only the root of the second element's name and then add the prefix denoting the number of its atoms and the suffix <em>-ide</em> (pentoxide). This is how we'll get dinitrogen pentoxide.
The only exception is methane (CH4), which is an organic compound. Organic compounds are named using the IUPAC nomenclature.
B) 50 J because it had less energy at the beginning than the end
Answer:

<u>A. Skin</u>
Explanation:
Skin unlike teeth, bones & shells is fragile & get decomposed easily under the soil.