Answer:
b.Rearrange the two equations to make each variable the focus (you will end up with three variations for each equation).
Physical, because the ice is only changing it's state. It's not changing to a new substance.
Answer: must have THE SAME number of atoms for each element
Explanation: Chemical equations must be balanced -- they must have the same number of atoms of each element on both sides of the equation. As a result, the mass of the reactants must be equal to the mass of the products of the reaction.
Answer: number of atoms is 5.21 · 10^24
Explanation: Atomic mass of Be is 9.012 g/mol.
Number of moles n = m/M = 78.0 g / 9.012 g/mol =
Multiply this with Avogadro number Na = 6.022*10^23 1/mol
Answer:
2.89 g/cm^3
Explanation:
Since density equals mass over volume (or also seen as 
), simply divide 66.5 grams by 23.0 cm. This will output an answer of 2.89 g/cm^3.
