Half-life of a radioactive substance is the time required to reduce the amount of substance to half of its initial amount.
In present case, half-life is material is given as 1000 years and initial amount of material is given as 400 kg
Answer 1) Since, half-life of radio-active substance is 1000 years, therefore after 1st half life, amount of the material will be left to half the initial amount. Hence, amount of substance left after 1000 years = 400/2 = 200 kg.
Answer 2) For 2000 years, radioactive material has crossed 2 times the half life. Therefore , amount of the material will be left to 1/4 the initial amount. Hence, amount of substance left after 2000 years = 400/4 = 100 kg.
Answer 3) For 4000 years, radioactive material has crossed 4 times the half life. Therefore , amount of the material will be left to 1/16 the initial amount. Hence, amount of substance left after 4000 years = 400/16 = 25 kg.
From the stomach, the food travels to the small intestine. This happens with the help of a movement known as peristalsis. Juices are released in the small intestine, which helps in the breakdown of carbohydrates, starch, and proteins.
Answer:
By a factor of 12
Explanation:
For the reaction;
A + 2B → products
The rate law is;
rate = k[A]²[B]
As you can see, the rate is proportional to the square of the concentration of A and the of the concentration of B
.
Let's say initially, [A] = x, [B] = y
The rate law in this case is equal to;
rate1 = k. x².y
Now you double the concentration of A and triple the concentration of B.
[A] = 2x, [B] = 3y
The new rate law is given as;
rate2 = k . (2x)². (3y)
rate2 = k . 4x² . 3y
rate2 = 12 k . x² . y
Comparing rate 2 and rate 1, the ratio is given as; rate 2/ rate 1 = 12
Therefore the rate has increased by a factor of 12.
Answer:
When two distinct elements are chemically combined—i.e., chemical bonds form between their atoms—the result is called a chemical compound. Most elements on Earth bond with other elements to form chemical compounds, such as sodium (Na) and Chloride (Cl), which combine to form table salt (NaCl).
B. The area of the island is your answer :)
