The number of half -lives that has passed after 105 hours for krypton-79 that has half-life of 35 hours is calculated as below
if 1 half life = 35 hours
what about 105 hours = ? half-lives
= (1 half life x105 hours) /35 hours = 3 half-lives has passed after 105 hours
Explanation:
The given data is as follows.
= 10 mM = 
M
= 750 ml, 
= 5 ml
= ?
Therefore, calculate the molarity of given NaCl stock as follows.
= 1.5 M
Thus, we can conclude that molarity of given NaCl stock is 1.5 M.
Answer:
B and C
Explanation:
I think the answer correct is C because you never know in what temperature the block of ice is going to melt but if it says select all that apply its possible that B might be useful.
Answer:
<em>so mass in gram=560grams</em>
Explanation:
number of moles=10moles
molar mass=56grams/moles
mass in gram of Fe=?
as we know that
<em>evaluating the formula</em>
<em>number of moles×molar mass=mass in gram</em>
<em>mass in gram=10moles×56grams/moles</em>
<em>mass in gram=560grams</em>
<em>i hope this will help you :)</em>
The answer is 7.33 g.
<span>To calculate this, we will use the the ideal gas law:
PV = nRT
where
P - pressure of the gas,
V - volume of the gas,
n - amount of substance of gas,
R - gas constant,
T - temperature of the gas.</span>
Since the amount of substance of gas (n) can be expressed as mass (m) divided by molar mass (M), then:
PV = RTm/M
It is given:
P = 0.98 atm
V = 10.2 l
T = 26°C = 299.15 K
R = 0.082 l atm/Kmol (gas constant)
M (H2O) = 2Ar(H) + Ar(O) = 2*1 + 16 = 2 + 16 = 18g
m = ?
Since PV = RTm/M, then:
m = PVM/RT
m = 0.98 · 10.2 · 18 / 0.082 · 299.15 = 179.928/24.5303 = 7.33 g
