Answer is: b. more than 7.
The endpoint is the point at which the indicator changes colour in a colourimetric titration and that is point when titration must stop.
For example, basic salt sodium acetate CH₃COONa is formed from the reaction between weak acid (in this example acetic acid CH₃COOH) and strong base (in this example sodium acetate NaOH).
Balanced chemical reaction of acetic acid and sodium hydroxide:
CH₃COOH(aq) + NaOH(aq) → CH₃COONa(aq) + H₂O(l).
Neutralization is is reaction in which an acid (in this example vinegar or acetic acid CH₃COOH) and a base react quantitatively with each other.
Answer: Thus the correct coefficient for sodium chloride is 2.
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The balanced chemical reaction is:
Thus the correct coefficient for sodium chloride is 2.
Answer: d. Remove one-half of the initial CaCO3.
Explanation: Le Chatelier's principle states that changes on the temperature, pressure, concentration and volume of a system will affect the reaction in an observable way. So in the reaction above:
A decrease in temperature will shift the equilibrium to the left because the reaction is exothermic, which means heat is released during the reaction. In other words, when you decrease temperature of a system, the equilibrium is towards the exothermic reaction;
A change in volume or pressure, will result in a production of more or less moles of gas. A increase in volume or in the partial pressure of CO2, the side which produces more moles of gas will be favored. In the equilibrium above, the shift will be to the left.
A change in concentration will tip the equilibrium towards the change: in this system, removing the product will shift the equilibrium towards the production of more CaCO3 to return to the equilibrium.
So, the correct answer is D. Remove one-half of the initial CaCO3.
Answer:
0.97014 moles KMnO4
Explanation:
1 g KMnO4 = 0.00633 mol
153.26 g x 0.00633 mol/ 1 g KMnO4 = 0.97014 moles KMnO4
Answer:
d. oxygen (O2) is the answer
