I think that the answer is 1/8 Hope this helps!!!! :D
Answer : The time required for decay is, 84 days.
Explanation :
Half-life of chromium-51 = 28 days
First we have to calculate the rate constant, we use the formula :



Now we have to calculate the time required for decay.
Expression for rate law for first order kinetics is given by:

where,
k = rate constant
t = time taken by sample = ?
a = let initial activity of the sample = 100
a - x = amount left after decay process = 12.5
Now put all the given values in above equation, we get


Therefore, the time required for decay is, 84 days.
In 1 mol of CH3OH, you have 4 H-atoms (because 3 H-atoms
are attached to the C-atom, and one H-atom in the OH group). That means
in 0.500 mol of CH3OH, you have 2 H-atoms since it is halved. And then we have Avogadro's constant: 6.02 * 1023.
The question asks for how many hydrogen atoms there are in 0.500 mol CH3OH. Using the numbers that we have (Avogadro's constant and no. of H-atoms), the answer of the question will be something like:
<span>H-atoms in CH3OH = 2 * 6.02 * </span>1023<span> = ~1.2 * 10</span>24
Answer:
7. .........................
Answer:
Option a → 4 mol NH₃
Explanation:
This the unbalanced reaction
NH₃ + O₂ ⟶ N₂ + H₂O
The balanced reaction:
4NH₃ + 3O₂ → 2N₂ + 6H₂O
4 mol of ammonia
3 mol of oxygen
2 mol of nitrogen
6 mol of water