Answer:
You cannot make observations if you are 57 seconds late into the lab.
Explanation:
The atomic nucleus can split by decay into 2 or more particles as a result of the instability of its atomic nucleus due to the fact that radioactive elements possess an unstable atomic nucleus.
Now, the primary particles which are emitted by radioactive elements in order to make them decay are alpha, beta & gamma particles.
The half life equation is;
N_t = N₀(½)^(t/t_½)
Where:
t = duration of decay
t_½ = half-life
N₀ = number of radioactive atoms initially
N_t = number of radioactive atoms remaining after decay over time t
We are given;
t = 57 secs
N₀ = 100 g
Now, half life of Nitrogen-16 from online sources is 7.2 seconds. t_½ = 7.2
Thus;
N_t = 100(1/2)^(57/7.2)
N_t = 0.4139g
We are told that In order to make observations, you require at least .5g of material.
The value of N_t you got is less than 0.5g, therefore you cannot make observations if you are 57 seconds late.
Answer: pretty sure it is D
Answer:
Explanation:
The rate of reaction will not depend upon concentration of reactant . It will be always constant and equal to .0089M s⁻¹.
Initial moles of reactant = 400 x 10⁻³ mole in 5 L
molarity = 400 x 10⁻³ /5 M
= 80 x 10⁻³ M .
= .08M
no of moles reacted in 2 s = .0089 x 2
= .0178 M
concentration left = .08 - .0178 M
= .0622 M .
No of moles left in 5 L
= 5 x .0622 = .31 moles .
