Answer:
n = 1.7 moles
Explanation:
Given mass, m = 23.8 grams
Molar mass of Nitrogen = 14 g/mol
Let there is n number of moles. We know that,
No. of moles = given mass/ molar mass
So, there are 1.7 moles in 23.8 grams of Nitrogen.
Answer is D
Explanation: A gamma ray primarily consists of pure energy and no mass.
Sucrose; C12H22O11
C9H8O4; acetyl salicylic acid
H2O2; hydrogen peroxide,
NaOH; sodium hydroxideExplanation:
The initial mass of sodium hydroxide is 3.3 g (answer C)
<u><em>calculation</em></u>
Step 1 : find the moles of iron (ii) hydroxide ( Fe(OH)₂
moles = mass÷ molar mass
from periodic table the molar mass of Fe(OH)₂ = 56 + [16 +1]2 = 90 g/mol
moles is therefore = 3.70 g÷ 90 g/mol = 0.041 moles
Step 2: use the mole ratio to calculate the moles of sodium hydroxide (NaOH)
from given equation NaOH : Fe(OH)₂ is 2 :1
therefore the moles of NaOH = 0.041 x 2 = 0.082 moles
Step 3: find mass of NaOH
mass = moles x molar mass
from the periodic table the molar mass of NaOH = 23 +16 +1 = 40 g/mol
mass = 0.082 moles x 40 g/mol = 3.3 g ( answer C)
