The element is Sr (strontium)
strontium is in atomic number 38 in the periodic table. Strontium has 2.8.8.8.8.2
it loses two electrons to become stable hence it has a charge of 2+. when strontium loses two electron it form ion with 36 electrons
Answer:

Explanation:
Hello.
In this case, we can solve this problem by applying the Boyle's law which allows us to understand the pressure-volume behavior as a directly proportional relationship:

In such away, knowing the both the initial pressure and volume and the final volume, we can compute the final pressure as shown below:

Consider that the given initial pressure is also equal to Pa:

Which stands for a pressure increase when volume decreases.
Regards.
Answer:
1. The energy intensity from the ruler going through the air
2. This one is pretty simple, you can add or take away things. This question is just asking you to list sounds from high pitch, to lowest pitch. Here are mine:
Timer
Microwave
Mouse clicking
Dog Barking
Voice
Typing
Knocking on door
Breathing
Foot Steps
Explanation:
I think it’s the one that has a Br
Answer:
2.038 seconds.
Explanation:
So, in the question above we are given the following parameters in order to solve this question. We are given a rate constant of 0.500 s^-, initial concentration= 0.860 M and final concentration= 0.310 M,the time,t =??.
Assuming that the equation for the first order of reaction is given below,that is;
A ---------------------------------> products.
Recall the formula below;
B= B° e^-kt.
Therefore, e^-kt = B/B°.
-kt = ln B/B°.
kt= ln B°/B.
Where B° and B are the amount of the initial concentration and the amount of the concentration remaining, k is the rate constant and t = time taken for the concentration to decrease.
So, we have; time taken,t = ln( 0.860/.310)/0.500.
==> ln 2.77/0.500.
==> time taken,t =2.038 seconds.