Strontium is the second element placed in the 5th period. It is an alkaline earth metal, a relatively reactive group, although not nearly as reactive as the alkali metals.
Gravity when the mantle cools it becomes heavier and therfore sinks
Answer:
0.2615 g
Explanation:
Given that mass of the body = 120 lb
The conversion of lb to g is shown below as:-
1 lb = 454 g
So, 120 lb = 120*454 g = 54480 g
The substance is of the human body
So, Mass of that substance in the body of mass 54480 g is:-
<u>0.2615 g of that substance would be found in the body of a person weighing 120 lb.</u>
The grams of oxygen that are required to produce 1 mole of H₂O is 16 g ( answer B)
<u><em> calculation</em></u>
2 CH₄ + 2NH₃ +3 O₂ → 2HCN + 6H₂O
step 1: use the mole ratio to find moles of O₂
from equation above the mole ratio of O₂: H₂O is 3:6 therefore the moles of O₂ = 1 mole x3/6 =0.5 moles
step 2: find mass of O₂
mass= moles x molar mass
from periodic table the molar mass of O₂ = 16 x2= 32 g/mol
mass O₂ = 0.5 moles x 32 g/mol = 16 g (answer B)