Answer:
Formula of magnesium oxide is MgO and formula of strontium oxide is SrO
Explanation:
Ca, Mg and Sr are same group bivalent metals.
Oxygen is a bivalent element
In general, formula of a compound made of a cation 
and an anion 
is 
for 
When x = y, formula of the compound becomes MA
As both these metals and oxygen are bivalent therefore formula of magnesium oxide is MgO and formula of strontium oxide is SrO.
Answer:
19.5g is the theoretical yield of alum
Explanation:
Based on the balanced reaction, 4 moles of sulfuric acid produce 2 moles of alum. To solve this question we need to find the moles of H2SO4. With these moles we can find the moles of alum and its mass assuming all sulfuric acid reacts producing alum.
<em>Moles Sulfuric Acid:</em>
8.3mL = 0.0083L * (9.9mol/L) = 0.08217 moles sulfuric acid
<em>Moles Alum:</em>
0.08217 moles sulfuric acid * (2mol KAl(SO4)2•12H2O / 4mol H2SO4) =
0.041085 moles KAl(SO4)2•12H2O
<em>Mass Alum -Molar mass: 474.3884 g/mol-</em>
0.041085 moles KAl(SO4)2•12H2O * (474.3884 g/mol) =
<h3>19.5g is the theoretical yield of alum</h3>
Answer:
1.61 × 10⁶ kJ
Explanation:
The human burns energy so as to be healthy.
The amount of energy burnt per day by an adult human is 2 × 20³ kcal per day. Since there is 24 hours in a day, the amount of energy burnt per hour is 2 × 20³ × 24 = 48 × 20³ kcal per hour.
The conversion rate of kcal to kJ is 1 kcal = 4.184 kJ. Therefore converting the kcal per hour to kJ per hour gives:
48 × 20³ × 4.184 = 200.882 × 20³ kJ = 1.61 × 10⁶ kJ
