Answer:
16400g
Explanation:
The amount of Calcium nitrate {Ca(NO3)2} that will be needed can be calculated as follows:
Molarity (M) = number of moles (n) ÷ volume (L)
According to this question, molarity = 0.2M, volume = 500L
number of moles = molarity × volume
number of moles (n) = 0.2 × 500
n = 100moles
Using mole = mass/molar mass
Molar mass of Ca(NO3)2 = 40 + {14 + 16(3)}2
= 40 + (14 + 48)2
= 40 + 62(2)
= 40 + 124
= 164g/mol
Mass = mole × molar mass
mass = 100 × 164
mass = 16400g of Ca(NO3)2
<h3><u>Answer;</u></h3>
Potassium-40 has a half life of 1.25 billion years.
<h3><u>Explanation;</u></h3>
New amount = Original amount × (1/2)^n ; where n is the number of half lives.
Original amount is 50 atoms
New amount is 25 atoms
Therefore;
25 = 50 × (1/2)^n
1/2 = (1/2)^n
Thus; n = 1
n = 1 which is equivalent to 1.25 billion years
Therefore;
<u>Potassium-40 has a half life of 1.25 billion years.</u>
Photosynthesis takes place in leaves. Leaves contain _C____ that allow for the exchange of gases during the process, and also help with the process of ___A___ .