Answer:
Explanation:
To separate the a mixture of chalk and potassium chloride, we must not that chalk is calcium carbonate compound, CaCO₃.
Calcium carbonate has low solubility in water. KCl is readily soluble in water and it is also an ionic compound.
To separate a mixture of compounds with various solubility, we can carryout dissolution, filtration and evaporation.
We first pour pure water into the mixture. Water will dissolve the potassium chloride readily.
Then using a filter paper we filter out the suspended chalk particles. Leave the filtrate to then dry and collect it.
The solution filtered should be evaporated to dryness. This will leave the KCl behind from the solution.
When CH₄ is burnt in excess O₂ following products are formed,
CH₄ + 2 O₂ → CO₂ + 2 H₂O
According to equation 1 mole of CH₄ (16 g) reacts with 2 moles of O₂ to produce 1 mole of CO₂ and 2 moles of H₂O. Hence the products are,
1 mole of CO₂ and 2 moles of H₂O
Converting 1 mole CO₂ to grams;
As,
Mass = Moles × M.mass
Mass = 1 mol × 44 g.mol⁻¹
Mass = 40 g of CO₂
Converting 2 moles of H₂O to grams,
Mass = 2 mol × 18 g.mol⁻¹
Mass = 36 g of H₂O
Total grams of products;
Mass of CO₂ = 44 g
+ Mass of H₂O = 36 g
-------------
Total = 80 g of Product
Result:
80 grams of product is formed when 16 grams of CH₄ is burnt in excess of Oxygen.
Answer:
B, (logic) D (knowledge)
Explanation:
Problem solving refers to the ability to figure out an answer to a question. The question can be general, such as how to design an experiment, or it can be more specific, such as how to calculate speed (its distance divided by time). Reasoning is closely related to problem solving. When scientists reason, they use logic and knowledge to make conclusions and decisions. The processes of reasoning and problem solving are usually more educational than the answer. Figuring something out is a wonderful workout for your brain.
(got this from the source)
Hope this helps!!!
