No, the formation of dew is condensation, which is a physical change.
<h2>Natural Abundance for 10B is 19.60%</h2>
Explanation:
- The natural isotopic abundance of 10B is 19.60%.
- The natural isotopic abundance of 11B is 80.40%.
- The isotopic masses of boron are 10.0129 u and 11.009 u respectively.
For calculation of abundance of both the isotopes -
Supposing it was 50/50, the average mass would be 10.5, so to increase the mass we need a more percentage of 11.
Determining it as an equation -
10x + 11y= 10.8
x+y=1 (ratio)
10x + 10y = 10
By taking the denominator away from the numerator
we get;
y = 0.8
x + y = 1
∴ x = 0.2
To get percentages we need to multiply it by 100
So, the calculated abundance is 80% for 11 B and 20% 10 B.
Answer:
True
Explanation:
The majority of the reactions happened with a flow of heat. When there's no heat, the reaction is adiabatic.
For no adiabatic reactions, the heat can be released (evolution) by the system, so the reaction will be exothermic, or absorbed by the system (absorption), then the reaction is called endothermic.
Answer:
Is removed from the atmosphere by photosynthesis.
Explanation:
The carbon dioxide (CO2) is presented in the atmosphere and its cycle began with it's incoming by respiration, combustion of fuels and decomposition. The autotrophs, which realize photosynthesis, use CO2 as fuel to produce their food with Sun rays.
The CO2 comprises about 0.3% of the atmospheric gases, and in the past few years, its input is being higher than its removal of the atmosphere, which is aggravating the greenhouse effect. Besides, the atmosphere of Venus has higher levels of CO2.
I think “A” is the right answer
