Precipitation and temperature
The exothermic process is a process or reaction that involves a release of energy from the system to its surroundings in various forms usually through heat, light, electricity or sound. In the four given choices, when melting a copper, you try to immerse the metal in heaping coals of fire. The metal will absorb the thermal energy coming from the coal, thus, once you retrieve the metal back, light will be emitted from it as well as heat.
Therefore, the answer is B. MELTING OF COPPER
Answer:
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Explanation:
<u>1. Chemical balanced equation (given)</u>
<u>2. Mole ratio</u>
This is, 1 mol of NaOH will reacts with 1 mol of KHP.
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<u>3. Find the number of moles in 72.14 mL of the base</u>
<u>4. Find the number of grams of KHP that reacted</u>
The number of moles of KHP that reacted is equal to the number of moles of NaOH, 0.007055 mol
Convert moles to grams:
- mass = number moles × molar mass = 0.007055mol × 204.23g/mol
You have to round to 3 significant figures: 1.44 g (because the molarity is given with 3 significant figures).
<u>5. Find the percentage of KHP in the sample</u>
The percentage is how much of the substance is in 100 parts of the sample.
The formula is:
- % = (mass of substance / mass of sample) × 100
- % = (1.4408g/ 1.864g) × 100 = 77.3%
Answer:
(a) False;
(b) False;
(c) False;
(d) True.
Explanation:
(a) When equilibrium is reached, the forward reaction rate becomes equal to the reverse reaction rate, that's why the molarity of each species remains constant, but reactions don't stop.
(b) According to the principle of Le Chatelier, an increase in molarity of either reactants or products would lead to a disturbance of equilibrium. This disturbance would lead to the shift of equilibrium towards the side which would minimize such a disturbance.
(c) Equilibrium constant is only temperature-dependent, it's independent of molarity, pressure, volume etc. of any species present in the reaction.
(d) The greater the initial molarity of reactants, the more products can be formed, e. g., since the ratio of products to reactants should be kept constant, the larger the amount of reactants, the greater the amount of products formed to keep a constant ratio.
