Answer:
D) cooling of the reaction mixture
Explanation:
Increase in temperature speedens the rate of a chemical reaction
Answer:
- <u>TRUE:</u> <em>Percent concentration is one of the most common and basic concentration measurement used by general public</em>
Explanation:
In chemistry there are many <em>concentration measurements</em> used to describe the mixtures. Some of them are, percent, molarity, molality, and molar fraction, among others.
Percent concentration is a popular one because it is commonly understood and used by the non specialist people, i.e. general public.
The percent concentration of a component is defined as: (amount of component in the mixture / amount of mixture) × 100.
The amounts may be measured in mass units (e.g grams) or volume units (e.g. mililiters).
For solutions, mass percent concentration is:
- % = (mass of solute / mass of solution) × 100.
And voluem percen contration is:
- % = (volume of solute / volume of solution) × 100
Since percentage is used in many profesional and personal activities, most persons use it.
For example, rubbing alcohol, that everyone buys in pharmacies, is 70%; vinager, used in the food, is acetic acid at 5% - 8%.
H2O or water, all humans are mostly mad of water and water covers most of the earth
Answer:
The combustion of 59.7 grams of methane releases 3320.81 kilojoules of energy
Explanation:
Given;
CH₄ + 2O₂ → CO₂ + 2H₂O, ΔH = -890 kJ/mol
From the combustion reaction above, it can be observed that;
1 mole of methane (CH₄) released 890 kilojoules of energy.
Now, we convert 59.7 grams of methane to moles
CH₄ = 12 + (1x4) = 16 g/mol
59.7 g of CH₄ 
1 mole of methane (CH₄) released 890 kilojoules of energy
3.73125 moles of methane (CH₄) will release ?
= 3.73125 moles x -890 kJ/mol
= -3320.81 kJ
Therefore, the combustion of 59.7 grams of methane releases 3320.81 kilojoules of energy
Answer:
Option B. Both have a pH less than 7, but H3PO4 has a lower pH than HCl
Explanation:
Those are acid, so the pH would be < 7.
H₃PO₄ is a weak acid with 3 dissociations
HCl is a strong acid.
pH depends on [H]⁺
H₃PO₄ → 3H⁺ + PO₄⁻³
HCl → H⁺ + Cl⁻
If both acid, have the same concentration, [H⁺]H₃PO₄ > [H⁺]HCl, that's why the pH from the phosphoric will be lower.
