Answer:
13 years
Explanation:
From;
0.693/t1/2 = 2.303/t log (No/N)
Where;
t1/12 = half-life of Cobalt-60 = 5.3 years
t = time taken = the unknown
No = mass of radioactive material originally present = 5.2 g
N = mass of radioactive material at time t = 0.95 g
Substituting values;
0.693/5.3 = 2.303/t log (5.2/0.95)
0.131 = 2.303/t(0.738)
0.131 = 1.6996/t
t = 1.6996/0.131
t = 12.97 years
t = 13 years(to the nearest whole number)
Answer:
Number of moles
Explanation:
Using the number of moles in chemical reactions, we can determine the quantity of products and even the reactants that are combining to form them.
The number of moles is derived using the expression below is;
Number of moles = 
Once we establish the number of moles of any of the specie given from the mass and molar mass, we can relate it to any other species.
The solid state where particles are more compact
We calculate it as follows:
Moles CO2 = 0.01849 g / 44 = 0.000420
<span>Mass C = 0.000420 x 12 = 0.00504 g </span>
<span>Moles H = 2 x 0.006232 / 18 = 0.000692 </span>
<span>Mass H = 0.000692 g </span>
<span>Mass O = 0.005982 - ( 0.00504 + 0.000692) = 0.00025 </span>
<span>Moles O = 0.00025 / 16 = 0.0000156 </span>
<span>C 0.000420
H 0.000692
O 0.0000156
</span>
<span>divide each by the smallest value, giving you the chemical formula as:
</span><span>
C27H44O</span>
Answer:
The correct matching of the air mass and the letters in the word bank are given as follows;
1. Warm and humid ↔ D
2. Extremely cold and dry ↔ B
3. Cold and dry ↔ A
4. Cold and humid ↔ C
5. Warm and dry ↔ E
Where;
A Represents continental polar
B Represents Artic
C Represents Maritime Polar
D Represents Maritime Tropical
E Represents Continental Tropical
Explanation:
A. A continental polar is one that can be described as a cold and dry climate as the region is located at a further away from the oceanic water bodies that add humidity to the climate
B. The regions of the Artic and the Antarctic have very limited amount of precipitation every year because the air is very cold as well as dry
C. A polar climate is a cold climate region, while a maritime climate is humid.
Therefore, the maritime polar climate combines both cold and humid conditions
D. A warm and humid region has high rainfall and humidity, as such the maritime climate which are humid and the tropical climate, which are warm, combine to give a warm and humid climate
E. The continental tropical climate can be described as warm and dry, compared to the continental water bodies, due to the location being distant from and therefore, the absence of high moisture containing wind that comes from the oceans.
