There are 1.078 x 10²³ molecules
<h3>Further explanation</h3>
Given
4 dm³ = 4 L Nitrogen gas
Required
Number of molecules
Solution
Assumptions on STP (1 atm, 273 K), 1 mol gas = 22.4 L, so for 4 L :
mol = 4 : 22.4
mol = 0.179
1 mol = 6.02 x 10²³ particles(molecules, atoms)
For 0.179 :
= 0.179 x 6.02 x 10²³
= 1.078 x 10²³
Answer:
the answer is 11
Explanation:
Ok, let us understand what is an atomic number, an atomic number is simply the proton number, the atomic number is always seen at the bottom left corner in a element of a periodic table, it is the number of proton in a atom of a certain element.
Density = mass / volume
19.3 = 13 / m
m = 13 / 19.3
m = 0.67g
<span>The correct answer is, Alkali Metals</span>
