Answer:
A. 28 years
Explanation:
Applying,
R = R'(2ᵃ/ⁿ).............. Equation 1
Where R = Original sample, R' = Sample left after decay, a = Total time taken to decay, n = half life.
From the question,
Given: R = 12 g, R' = 6 g, a = 28 years.
Substitute into equation 1 and solve for n
12 = 6(2²⁸/ⁿ)
12/6 = 2²⁸/ⁿ
2²⁸/ⁿ = 2
Equation the base,
28/n = 1
n = 28 years.
Hence the half-life is 28 years
Answer:
large supply of nutrients.
Explanation:
In a wetland, the soil is covered by water or is almost covered by water. This water may be coming upwards from an underground aquifer. Wetlands are covered by water for most of the year.
They are sheltered waters and do provide habitats for many living things.
Nutrients such as; Carbon sulfur, phosphorus, carbon, and nitrogen are cycled within the soil of wetlands hence wetlands have a large supply of nutrients.
You can find an element's amount of energy level by determining their place on the periodic table. An element's amount of energy levels are represented by which period/ row they are in. For example, Calcium has 4 energy levels. I know this because it is in the fourth period on the table.
Hope this helps!
Answer:
The reaction is exothermic.
Yes, released.
The heat released is 4,08x10³ kJ.
Explanation:
For the reaction:
C₃H₈(g) + 5O₂(g) → 3CO₂(g) + 4H₂O(l)
The ΔH is -2220 kJ, As ΔH is <0, <em>The reaction is exothermic.</em>
As the reaction is exothermic, the heat of the reaction will be <em>released.</em>
The heat released in 81,0g is:
81,0g C₃H₈×
×
= <em>4,08x10³ kJ</em>
<em>-Using molar mass of C₃H₈ to convert mass to moles and knowing that there are released 2220 kJ per mole of C₃H₈-</em>
I hope it helps!
