To answer this we need to assume that at STP 1 mol of a substance is equal to 22.4 L. We use this data for the calculations.
Statement 1
2 mol HCl (1 mol H2 / 2 mol HCl) = 1 mol H2 thus at STP 22.4 L H2
<em>This statement is false.</em>
Statement 2
1 L Zn (1 mol Zn / 22.4 L Zn) (1 mol H2 / 1 mol Zn) (22.4 L H2 / 1 mol H2) = 1L H2
<em>This statement is true.</em>
Statement 3
65.39 g Zn (1 mol Zn / 65.39 g Zn) (1 mol H2 / 1 mol Zn) = 1 mol H2
<em>This statement is true.</em>
Statement 4
1L HCl (1 mol HCl / 22.4 L HCl)(1 mol H2 / 2 mol HCl) = 0.022 mol H2
<em>This statement is false.</em>
Answer:
The correct answer is "142 g".
Explanation:
According to the question,
⇒ 
where,
Z = 2
F = 96500c
C = 30 A
t = 4h
= 
= 
We know that,
Atomic mass of Cu(M) = 63.5 g/mole
Now,
⇒ 
On putting the values, we get
Answer:
Ninguno estará en el agua después de 15 minutos.
Explanation:
Tomar 25 + 30 = 55 por minuto de agua que sale. Como ahora sabemos eso, tómese 55 minutos por 15 minutos. Debe obtener 825, por lo tanto, no quedará agua.
- Avíseme si esto es incorrecto o si desea una explicación más detallada. Espero que esto haya ayudado!
<h3>
Answer:</h3>
#1. 50 g
#2. 25 g
#3. 4 half lives
<h3>
Explanation:</h3>
<u>We are given;</u>
- Original mass of a radioisotope as 100 g
- Half life of the radioisotope as 10 years
We need to answer the questions:
#a. Mass remaining after 10 years
Using the formula;
Remaining mass = Original mass × 0.5^n , where n is the number of lives.
In this case, since the half life is 10 years then n is 1
Therefore;
Remaining mass = 100 g × 0.5^1
= 50 g
Therefore, 50 g of the isotope will remain after 10 years
#b. Mass of the isotope that will remain after 20 years
Remember the formula;
Remaining mass = Original mass × 0.5^n
n = Time ÷ half life
n = 20 years ÷ 10 years
= 2
Therefore;
Remaining mass = 100 g × 0.5^2
= 25 g
Thus, 25 g of the isotope will be left after 20 years
#3. Number of half lives in 40 years
1 half life = 10 years
But; n = time ÷ half life
= 40 years ÷ 10 years
= 4
Thus, the number of half lives in 40 years is 4.
