Answer:
The time taken for the cross mark to disappear decreases steadily down the column.
Explanation:
Now if we look at the data provided, we will discover that the volume of the HCl was held constant while the volume of the thiosulphate was increased steadily and the volume of water decreased steadily.
Recall that a system is more concentrated when it contains less volume of water and more volume of reactants. Hence as the volume of water in the system is being reduced, the concentration of reactants is increased.
It has been established that an increase in the concentration of reactants lead to an increase in the rate of reaction. The disappearance of the cross shows the completion of the reaction between HCl and thiosulphate. The faster or slower the cross disappears, the faster or slower the rate of reaction.
Since increase in concentration of reactants increases the rate of reaction, it is observed that as the volume of the thiosulphate increases (reactant concentration increases) the cross disappears faster (rate of reactant increases). Hence as the volume of thiosulphate increases, it takes a shorter time for the cross to disappear. This implies that the time column in the table (refer to the question) will decrease steadily as the volume of thiosulphate increases.
<u>Answer:</u> Zinc will react with lead (II) nitrate solution.
<u>Explanation:</u>
Single displacement reaction is defined as the reaction in which more reactive element displaces a less reactive element from its chemical reaction.
The reactivity of metal is determined by a series known as reactivity series. The metals lying above in the series are more reactive than the metals which lie below in the series.
General equation for single displacement reaction follows:

When zinc is reacted with calcium nitrate, the reaction does not take place as zinc is less reactive than calcium. Zinc lies below in the series than calcium.

But, when zinc is reacted with lead (II) nitrate, the reaction do take place as zinc is more reactive than lead. Zinc lies above in the series than lead.
The chemical equation for the reaction of zinc and lead (II) nitrate follows:

Hence, zinc will react with lead (II) nitrate solution.
Answer:
As
Explanation:
For any element to exhibit the pattern of ionization energy shown in the question, it must possess five electrons in its outermost shell. These five electrons are not lost at once. They are lost progressively until the valence shell becomes empty. The ionization energy increases steadily as more electrons are lost from the valence shell.
The only pentavalent element among the options in arsenic, hence the answer.
Answer: 3 moles solute x 1 dm^3/0.60 moles solute = 5 dm^3
Explanation:
273 Kelvin, 0 degrees Celsius, 32 degrees Fahrenheit