Answer:
So, Luke and Sian has to increase the pH of the soil by adding base to it.
Explanation:
The pH is defined as the negative logarithm of the hydrogen ion concentration in their aqueous solution.
![pH=-\log[H^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%5BH%5E%2B%5D)
- With increase in hydrogen ion concentration the pH value decreases.
- With decrease in hydrogen ion concentration the pH value increases.
The pH of the soil after testing it on a kit comes out be 5.0, but they both need pH of the soil to 6.5.
Comparison of pH of soil:
= 5.0 < 6.5
= High hydrogen ion concentration > High hydrogen ion concentration
So, Luke and Sian has to increase the pH of the soil by adding base .Doing so will decrease the hydrogen ion concentration in the soil (where as addition of acid lower the pH of soil).
Answer:
d. Copper (II) sulfate
Explanation:
Given data:
Mass of Al = 1.25 g
Mass of CuSO₄ = 3.28 g
What is limiting reactant = ?
Solution:
Chemical equation:
2Al + 3CuSO₄ → Al₂ (SO₄)₃ + 3Cu
Number of moles of Al:
Number of moles = mass/molar mass
Number of moles = 1.25 g/ 27 g/mol
Number of moles = 0.05 mol
Number of moles of CuSO₄:
Number of moles = mass/molar mass
Number of moles = 3.28 g/ 159.6 g/mol
Number of moles = 0.02 mol
now we will compare the moles of reactant with product.
Al : Al₂ (SO₄)₃
2 : 1
0.05 : 1/2×0.05=0.025 mol
Al : Cu
2 : 3
0.05 : 3/2×0.05 = 0.075 mol
CuSO₄ : Al₂ (SO₄)₃
3 : 1
0.02 : 1/3×0.02=0.007 mol
CuSO₄ : Cu
3 : 3
0.02 : 0.02
Less number of moles of reactants are produced by CuSO₄ thus it will act as limiting reactant.
Energy lost to condense = 803.4 kJ
<h3>Further explanation</h3>
Condensation of steam through 2 stages:
1. phase change(steam to water)
2. cool down(100 to 0 C)
1. phase change(condensation)
Lv==latent heat of vaporization for water=2260 J/g

2. cool down
c=specific heat for water=4.18 J/g C

Total heat =

Weathering is the process by which rocks are broken down by either physical or chemical means. Physical weathering involves physical factors that cause mechanical break down of rocks while chemical weathering involves chemical reactions between the contents of the rocks and other factors such air (oxygen). Agents of weathering are the factors that cause or enhance both physical and chemical weathering. Some of these factors cause both physical and chemical weathering these includes water and temperature.
Holding items in the freezer for too long is not an example of abuse of time and temperature.
<h3>
What is abuse of time and temperature?</h3>
Abuse of time and temperature has to do with a situation in which time is used in an improper way or food is not held at the correct temperature ultimately leading to food poisoning.
Holding items in the freezer for too long is not an example of abuse of time and temperature.
Learn more about temperature: brainly.com/question/7510619