Answer:
The answer is "Option B"
Explanation:
Formula:
Na atoms= Na atoms moles \times NA
<span>0.228 g
The balance formula for the reaction between SrH2 and H2O is
SrH2(s) + 2 H2O(l) ==> Sr(OH)2(s) + 2 H2(g)
So for every mole of SrH2 used, 2 moles of hydrogen gas, or 4 moles of hydrogen atoms are released. So let's calculate the molar mass of SrH2 and H2O so see what the limiting reactant is.
strontium = 87.62
Hydrogen = 1.00794
Oxygen = 15.999
Molar mass of SrH2 = 87.62 + 2 * 1.00794 = 89.63588 g/mol
Molar mass of H2O = 2 * 1.00794 + 15.999 = 18.01488 g/mol
Moles of SrH2 = 5.06 g / 89.63588 g/mol = 0.056450609 mol
Moles of H2O = 4.34 g / 18.01488 g/mol = 0.240911957 mol
Looking at the balanced formula, for every mole of SrH2, it takes 2 moles of H2O. So the limiting reactant will be the SrH2. And for every mole of SrH2 used, we get 4 moles of hydrogen atoms. So
4 * 0.056450609 mole * 1.00794 g/mole = 0.227595307 g
Since we only have 3 significant figures, round the result to 3 figures, giving
0.228 g</span>
Answer:
Pure Chemistry -- is NOT considered a branch of Chemistry.
Explanation:
Second question is number 4.
B. nuclear to thermal to mechanical to electrical
Answer: Metals found as native minerals in nature are not highly reactive
Explanation:
Native minerals refers to minerals that are found in nature in their pure metallic form such as gold. Iron and aluminum are highly reactive metals. Highly reactive metals are far up in the activity series of metals, they have a great tendency towards oxidation. On the other hand, noble metals have less tendency towards oxidation and are found close to the bottom of the activity series for example, gold.
