Electronic Configuration of elements in a period is same because If you see the electronic Configuration of elements in a period you will notice that the valence shell electrons for all elements are present in the same Shell. For example, in first period consisting of Hydrogen and Helium, both the elements' valence electrons are present in the same Shell.
Electronic Configuration of Hydrogen,
1s^1
Electronic Configuration of Helium,
1s^2
Both elements' valance electrons are present in the 1st shell
(This is just a small example to understand the concept because other periods are long but the first period is short that's why I gave the example of the first period)
Does it is a complete qwestion? It
is not clearef
Becky's speed is her distance travelled which is 30 km divided by her time travelled of 2.5 hours which gives her average speed of 12 km/hour which is a quite good speed if she was say riding a bicycle and which would give her a good aerobic workout.
Yes, it will be worthwhile to investigate finding a catalyst to use in this reaction under standard conditions because it is negative.
<h3>What is a Catalyst?</h3>
This is a substance which speeds up the rate of a chemical reaction by lowering the activation energy.
ΔG being negative indicates a a slow reaction which is why a catalyst under standard conditions should be used.
Read more about Catalyst here brainly.com/question/12507566
#SPJ1
The answer is (3). The number of Sr is the same so if the compound has the smallest gram formula mass, it has the highest percent composition by mass of strontium. So the answer is (3).