Answer:
D. 0.75 grams
Explanation:
The data given on the iridium 182 are;
The half life of the iridium 182,
= 15 years
The mass of the sample of iridium, N₀ = 3 grams
The amount left, N(t) after two half lives is given as follows;

For two half lives, t = 2 × 
∴ t = 2 × 15 = 30


∴ The amount left, N(t) = 0.75 grams
Answer:
The answer is D.
Explanation:
Intermolecular force are negligible
When the distance between molecules decrease,
the attraction or repulsion become greater
Answer: 4.5 x 10e-7
Explanation: 450 x 1e+9 = correct answer
Multiply amount of nanometers by 1e+9 to get the approximate result in meters.
Answer : The correct option is, (b) occur when there is more free energy in the reactants than the products.
Explanation :
Endergonic reactions : It i defined as the reaction in which the energy is absorbed during the reaction.
In endergonic reactions, the Gibbs free energy of product is lower than the reactants. That means, ΔG > 0 and the reaction is non-spontaneous.
Exergonic reactions : It i defined as the reaction in which the energy is released during the reaction.
In exergonic reactions, the Gibbs free energy of product is greater than the reactants. That means, ΔG < 0 and the reaction is spontaneous.
Hence, the endergonic reactions is occur when there is more free energy in the reactants than the products.
<span>The rate of effusion of a gas is inversely proportional to the square root of the molecular weight of the species. Now there will be differences among isotopomers but neglecting these and taking the avg mol wt of N2 = 28 and Xe = 132;
Rate(N2)/Rate(Xe) = sqrt (132/28) = 2.17</span>