5 is 2 I’m not sure about 4 though....
<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.
The answer is <span>B. nonpolar.
Polar molecules dissolve best in polar solvents while nonpolar molecules dissolve best in nonpolar solvents. </span>Oils are nonpolar. So, they will dissolve best in nonpolar solvents. If you put oil in some polar solvent, such as water, it will hardly dissolve.
Benzene is the compound name and it is a covalent compound
I have attached a paper with the answer. hope you understand. let me know if you have any question
