<h2>
Answer: # of neutrons = 9</h2>
<h3>
Explanation:</h3>
# of neutrons = mass number - atomic number
= 17 - 8
= 9
<h3>∴ number of neutrons in an atom of oxygen of mass number 17, is 9.</h3>
The Half life is the time taken for a radioisotope or a radioactive substance to decay by half its original amount. The half life of carbon 14 is 5600 years.
Original mass is 100%
Remaining amount is 24%
Therefore; 0.24 = 1 × (1/2)^n
n = log 0.24/log 0.5
= 2.06
therefore, the age of the fossil is 5600×2.06
= 11529.8
≈ 11529 years
Answer:
Mass = 11.78 g of P₄
Explanation:
The balance chemical equation is as follow:
6 Sr + P4 → 2 Sr₃P₂
Step 1: Calculate moles of Sr as;
Moles = Mass / M/Mass
Moles = 50.0 g / 87.62 g/mol
Moles = 0.570 moles
Step 2: Find moles of P₄ as;
According to equation,
6 moles of Sr reacted with = 1 mole of P₄
So,
0.570 moles of Sr will react with = X moles of P₄
Solving for X,
X = 1 mol × 0.570 mol / 6 mol
X = 0.0952 mol of P₄
Step 3: Calculate mass of P₄ as,
Mass = Moles × M.Mass
Mass = 0.0952 mol × 123.89 g/mol
Mass = 11.78 g of P₄
Foods are a solid we need to survive
methanol:
1 mole CH3 OH --> produces --> 1 mole CO2
1 mole CO2 has a molar mass of 44.01 gh/mole
your set up is:
(44.01 g CO2) / -726.5kJ = 0.06058g
your answer 0.06058 grams of CO2 produced per kJ released.
