<h3>Answer:</h3>
18.75 grams
<h3>Explanation:</h3>
- Half-life refers to the time taken by a radioactive material to decay by half of the original mass.
- In this case, the half-life of element X is 10 years, which means it takes 10 years for a given mass of the element to decay by half of its original mass.
- To calculate the amount that remained after decay we use;
Remaining mass = Original mass × (1/2)^n, where n is the number of half-lives
Number of half-lives = Time for the decay ÷ Half-life
= 40 years ÷ 10 years
= 4
Therefore;
Remaining mass = 300 g × (1/2)⁴
= 300 g × 1/16
= 18.75 g
Hence, a mass of 300 g of an element X decays to 18.75 g after 40 years.
<u>Answer:</u> The molar solubility of MX is 
<u>Explanation:</u>
We are given:

The chemical equation for the ionization of MX follows:

S S
The expression of
for above equation is:
......(1)
The chemical equation for the ionization of
follows:

0.25M 0.5M 0.25M
Total concentration of cation from both the equation is:
![[M^+]=0.5+S](https://tex.z-dn.net/?f=%5BM%5E%2B%5D%3D0.5%2BS)
As,
, so S is also very very less than 1 and can be easily neglected.
So, ![[M^+]=0.5M](https://tex.z-dn.net/?f=%5BM%5E%2B%5D%3D0.5M)
Putting values in equation 1, we get:

Hence, the molar solubility of MX is 
Answer:
Kinetic energy has a direct relationship with mass, meaning that as mass increases so does the Kinetic Energy of an object. ... Objects with greater mass can have more kinetic energy even if they are moving more slowly, and objects moving at much greater speeds can have more kinetic energy even if they have less mass
Answer:
1500 mmol.
Explanation:
Hello,
In this case, for such monovalent potassium species, we can verify that 1 mEq equals 1 mmol, therefore, the required solution is shown below:

Which means that also 1500 mmol of monovalent potassium ions are contained in the liter.
Regards.