Answer:
a. first-order in both A and B.
Explanation:
In order to determine the kinetics of reaction let us consider the given data
a) Doubling the concentration of B while keeping the concentration of A fixed doubles the rate of the reaction. : it means the reaction is first order reaction with respect to reactant B.
b) The half life is the time required to complete the reaction by half way.
As with time one half of A remains and after equal time one fourth of A remains it means again the order of reaction is first with respect to A also.
There is no effect on the half life if we are decreasing the initial concentration of A also.
Answer:
1) 0.00498 mol Cu.
2) 0.00000374 mol CO₂
Explanation:
Question 1)
We want to convert 3.00 * 10²¹ copper atoms into moles. Note that 3.00 is three significant figures.
Recall that by definition, one mole of a substance has exactly 6.022 * 10²³ amount of that substance. In other words, we have the ratio:

We are given 3.00 * 10²¹ Cu. To cancel out the Cu, we can multiply it by our above ratio with Cu in the denominator. Hence:

Cancel like terms:

Simplify:

Use a calculator:

Since the resulting answer must have three significant figures:

So, 3.00 * 10²¹ copper atoms is equivalent to approximately 0.00498 moles of copper.
Question 2)
We want to convert 2.25 * 10¹⁸ molecules of carbon dioxide into moles. Note that 2.25 is three significant digits.
By definition, there will be 6.022 * 10²³ carbon dioxide molecules in one mole of carbon dioxide. Hence:

To cancel the carbon dioxide from 2.25 * 10¹⁸, we can multiply it by the above ratio with the carbon dioxide in the denominator. Hence:

Cancel like terms:

Simplify:

Use a calculator:

Since the resulting answer must have three significant figures:

So, 2.25 * 10¹⁸ molecules of carbon dioxide is equivalent to approximately 0.00000374 moles of carbon dioxide.
Answer:
D) Bees and plants or sea anemonies and clownfish.
i think..
Explanation:
Physical change. Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. ... Physical changes occur when objects or substances undergo a change that does not change their chemical composition.
Answer: Xe, Kr, Ar, Ne
Explanation:
Hope i helped please mark brainliest!