<span>What caused the bubbles to form when you added the catalyses to the hydrogen peroxide and water mixture at 40 °C? A. Catalyses activity heated the solution to its boiling point. B. Hydrogen gas formed during the formation of hydrogen peroxide. C. Oxygen gas formed during the decomposition of hydrogen peroxide.
This would be the water, mixture.</span>
<u>Ans: 650 J = 155 calories</u>
<u>Given:</u>
Energy in joules = 650 J
<u>To determine:</u>
The energy in calories
<u>Explanation:</u>
1 joule = 0.2388 calories
Therefore, 650 joules = 0.2388 calories * 650 J/1 J = 155 calories
A 1.775g sample mixture of KHCO₃ is decomposed by heating. if the mass loss is 0.275g, the mass percentage of KHCO₃ is 70.4%.
<h3>What is a decomposition reaction?</h3>
A decomposition reaction can be defined as a chemical reaction in which one reactant breaks down into two or more products.
- Step 1: Write the balanced equation for the decomposition of KHCO₃.
2 KHCO₃(s) → K₂CO₃(s) + CO₂(g) + H₂O(l)
The mass loss of 0.275 g is due to the gaseous CO₂ that escapes the sample.
- Step 2: Calculate the mass of KHCO₃ that formed 0.275 g of CO₂.
In the balanced equation, the mass ratio of KHCO₃ to CO₂ is 200.24:44.01.
0.275 g CO₂ × 200.24 g KHCO₃/44.01 g CO₂ = 1.25 g KHCO₃
- Step 3: Calculate the mass percentage of KHCO₃ in the sample.
There are 1.25 g of KHCO₃ in the 1.775 g sample.
%KHCO₃ = 1.25 g/1.775 g × 100% = 70.4%
A 1.775g sample mixture of KHCO₃ is decomposed by heating. if the mass loss is 0.275g, the mass percentage of KHCO₃ is 70.4%.
Learn more about decomposition reactions here: brainly.com/question/14219426
Water is held together by hydrogen bonds.
Water molecule: H2O:
--- = hydrogen bond
O
/ \
H H ---O
/ \
H H