Answer:
7.941
Explanation:
You can look at a picture of the periodic table.To calculate the atomic mass of a single atom of an element, add up the mass of protons and neutrons. Example: Find the atomic mass of an isotope of carbon that has 7 neutrons. You can see from the periodic table that carbon has an atomic number of 6, which is its number of protons.
Hope I helped
Answer:
B: Presence of ashes
Explanation:
Burning molecules turns them into other molecules
Mass of X produced : D. 4.6 g
<h3>Further explanation</h3>
Reaction
Decomposition of Magnesium nitrate into Magnesium oxide, Oxygen, and Nitrogen oxides
2 Mg(NO₃)₂ → 2 MgO + 4 NO₂ + O₂
mol Magnesium nitrate-Mg(NO₃)₂(MW=148,3 g/mol) :
mol ratio Mg(NO₃)₂ : NO₂ = 2 : 4, so mol NO₂ :
mass NO₂(MW=46 g/mol) :
.
C. Heat answer correct that