Answer:
The percentage of the block contains 15% after 60 years.
Explanation:
Step 1: Formula for half-life time
To calculate the half-life time we will use the following formula:
At = A0 * 1/2 ^(x/t)
With At = the quantity after a time t
A0 = The quantity at time t = 0 (start)
x = time in this case = 60 years
t= half-life time = 22 years
Step 2: Calculate the percentage after 60 years
In this case: after 60 years the percentage will be
A0= 10 * 1/2 ^(60/22)
A0 = 1.5
A0 / At = 1.5 /10 = 0.15
0.15 *100% = 15 %
The percentage of the block contains 15% after 60 years.
Hey there!:
Molar mass CO2 = 44.01 g/mol
44.01 g CO2 ------------------- 6.02*10²² molecules CO2
88 g CO2 ------------------------ y
y = 88 * ( 6.02*10²² ) / 44.01
y = 5.29*10²⁵ / 44.01
y = 1.2 * 10²⁴ molecules of CO2
Answer A
Hope that helps!
Answer:
1. conduction
2. radiation
3.convection
4. conduction?
5. radiation
6. convection
7. convection
8. convection
9. radiation
10.radiation
(sorry if they aren't all correct)
