Use formula n= number of particles / avogrado constant
n= number of mole
avogrado constant= 6.12x10^-23
you will get 2.042 x 10^52
Answer:
0.033 M
Explanation:
Let's consider the neutralization reaction between NaOH and HCl.
NaOH + HCl → NaCl + H₂O
0.4 L of 0.1 M NaOH were used. The reacting moles of NaOH are:
0.4 L × 0.1 mol/L = 0.04 mol
The molar ratio of NaOH to HCl is 1:1. The reacting moles of HCl are 0.04 moles.
0.04 moles of HCl are in 1.2 L. The molarity of HCl is:
M = 0.04 mol / 1.2 L = 0.033 M
Answer:- 9.4 minutes.
Solution:- Radioactive decay obeys first order reaction kinetics and the equation used to solve this type of problems is:

where, k is decay constant and t is the time.
is the initial amount of the radioactive substance and N is the remaining amount.
Since the value of decay constant is not given, so we need to calculate it first from given half life by using the formula:

where
stands for half life.
Given half life is 3.0 minutes.
So, 

Let's plug in the values in the first order reaction equation and solve it for t.

It could also be written as:



k = 9.4 min
So, the radioactive substance would take 9.4 minutes to decay from 40.0 grams to 4.5 grams.
Answer:
e. 4.847 x 10-19 J
Explanation:
From the given information:
The equation connecting the photon energy and the wavelength is:

where;
= 6.626 * 10 ^{-34} J.s
= 3.00 * 10^8 m/s
wavelength 

To determine the photon energy of violet light

= 4.847 × 10⁻¹⁹ J
There will be seven characters so the answer is e