1.) K - potassium
2.) Ca - calcium
3.) Ni - nickle
4.) Cu - copper
5.) Ag - silver
6.) Au - gold
following the reactivity series from most to least reactive.
Answer:
D. 400 cal
Explanation:
Spec heat of water 1 cal/gm-C
1 cal / gm-C * 100 gm * ( 20-16 C) = 400 cal
Answer:
Blue
Explanation:
If you look at a flame, blue is always at the bottom right? So that would be common sense that blue would be the hottest.
<span>Answer : The average atomic mass of rubidium = 85.468
Explanation: Given that 85Rb isotope has atomic mass of 84.912amu with abundance of 72.17%
therefore we get 84.912 x 0.7217 = 61.281
and 87Rb isotope has atomic mass of 86.909 with abundance of 27.83%
hence we get 86.909 x 0.2783 = 24.187
Thus we get 61.281 + 24.187 = 85.468 as the average atomic mass of Rubidium.</span>
Answer:
The time decreases steadily
Explanation:
We know that the rate of chemical reaction is defined as how fast or slow a chemical reaction proceeds. Hence a chemical reaction is said to proceed at a faster rate if it takes a lesser time for the reaction to get to completion.
There are certain factors that affects the rate of reaction, prominent among them is the concentration of reactants. Concentration simply means the amount of substance in a system.
Taking a look at the table given in the question, we will realize that the volume of HCl remained constant, the volume of thiosulphate increased steadily while the volume of water decreased steadily. Remember that concentration increases when less water is added to the system. This implies that the reactant concentration increases steadily. Hence, according to the collision theory, particles collide more frequently and the rate of reaction increases.
As the rate of reaction increases, it now takes a lesser time for the reaction to get to completion (indicated by the disappearance of the cross). Hence as we move down the table, it takes lesser and lesser time for the cross to disappear. This means that the column for time will decrease steadily.
