Answer:
The correct answer is B it"s a proven fact.
Explanation:
Any scientific theory is based upon many experiments ans observations.The experiment and observations are repeated many times to provide a scientific logic about that theory.
A scientific theory is accepted only when that theory is logically proved by various experiment ,observations,statistical analysis etc.
Fire is actually a chemical reaction. It's an oxidation reaction to be specific. When wood gets hot enough (the part of the wood that is burning) the large hydrocarbons break down to charred solids and a gas. The gas is what reacts with oxygen in the atmosphere to produced light, CO2 and H2O.
Answer:
When a candle burns, the hydrogen and carbon from the wax combine with the oxygen in the air to become carbon dioxide and water vapor. Most of the matter in the candle ends up as these two gases.
Answer:
The answer to your question is: B. Nickel Sulfate
Explanation:
A. Nickel sulfur oxide this compound do not exist, this option is incorrect.
B. Nickel sulfate This compund exist and the formula is NiSO₄
C. Nickel oxygen sulfide This compound do not exist, the order of the names is inocrrect.
D. None of these This option is incorrect because because letter B is correct.
Answer:
Explanation:
A foam coffe cup is considered a perfectly insulated system: heat energy is not exchanged with the surroundings.
Under that assumption, the heat released by the chemical reaction is equal to the heat absorbed by the system.
1. Heat absorbed by the system:
Use the equation Heat = Q = m × C × ΔT, with:
- m = 126 g (the amount of solution produced)
- C = specific heat of pure water = 4.186 J/gºC
- ΔT = increase of temperature = 24.70 ºC - 21.00ºC = 3.70ºC
Q = 126g × 4.186J/gºC × 3.70ºC = 1,951.5J
<em><u></u></em>
<em><u>2. Enthalpy of the reaction</u></em>
The enthalpy must be reported in kJ/mol.
Then, convert juoles to kilojoules, dividing by 1,000; and divide by 2.00 moles, which is the amount of compound that reacted:
- ΔHrxn = 1,951.5J × (1kJ / 1,000J) × (1 / 2mol) ≈ 0.9758 kJ/mol
Round to <em>3 significant figures</em>: 0.976 kJ/mol
