Answer:
Oxygen is the most contain in earth but you asked in a,b,c and d. So I'll choice A. aluminium.
D. They all contain carbon as an important part of their structure.
Radioactive material undergoes 1st order decay kinetics.
For 1st order decay, half life = 0.693/k
where k = rate constant
k = 0.693/half life = 0.693/8.02 = 0.0864 day-1
Now, for 1st order reaction,
k =

Given: t = 6.01d, initial conc. = 5mg
∴0.0864 =

∴ final conc. = 2.975 mg
Answer:
last choice
Explanation:
oxidation and reduction can be defined in terms of adding or removing oxygen to a compound
oxidation is gaining oxygen
reduction is to loss oxygen
3. 4 g of a nonelectrolyte dissolved in 78. 3 g of water produces a solution. The molar mass of the solute will be 17.94.
<h3>
What is molar mass?</h3>
Molar mass of a substance is its mass in grams in per mole of a solution.
Freezing point: Freezing point of a substance is a temperature at which a liquid starts to solidify.
Depression in the freezing point can be calculated
[Depression in freezing point of pure solvent—Freezing point of solution] =[(0) - (-4.5)] °C =4.5 °C
molar mass = Number of moles of solute m / Mass of solvent in Kg
3.4g / M x 1/ 0.0783 kg = 43.42
Substitute AT by 4.5°C , Kr by 1.86 °C/m, and m by 43.42 m in equation (1) as follows:
1.86 x 43.42 / 4.5 = 17.94
Therefore, molar mass of solute to be 17.94.
To learn more about molar mass, refer to the link:
brainly.com/question/22997914
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