<span>3.68 x 10²⁵ bromine atoms * 1mol/6.02*10²³ atoms=
= 61.13 mol of bromine atoms
1 mol PBr3 ----- 3 mol Br
x mol PBr3 -----61.13 mol Br
x= 1*61.13/3 = 20.4 mol PBr3.
</span>20.4 mol PBr3 <span>contain 3.68 x 10^25 bromine atoms.</span>
Answer:
d.) Microwave photons cause the molecules to increase their rotational energy states, whereas infrared photons cause electrons in the molecules to increase their electronic energy states.
Explanation:
Microwave: transitions in the molecular rotational levels
Infrared: transitions in molecular vibrational levels
UV/Visible: transitions in electronic energy levels.
Answer:
The statement that describes the gas of neon is
1. They are far apart.
2. They move constantly.
3. They move freely in all directions.
4. They move at high speed. Neon is termed as a chemical element. It is a noble gas.
It is odorless, colorless, inert monatomic gas when under standard condition. Neon is the second of the rare gases to be discovered. The second lightest inert gas.
Explanation:i just know oki
Answer: A) Bent or angular, polar
Explanation:
The central atom oxygen has two lone pairs and two bond pairs in
. The number of electron pairs are 4, that means the hybridization will be
and the electronic geometry of the molecule will be tetrahedral. But as there are two lone pair of atoms around the central oxygen atom, repulsion between lone and bond pair of electrons is more and hence the molecular geometry will be bent shape.
The compound
is polar as the net dipole moment of oxygen - fluoride bonds do not cancel each other out.
Answer:
4 g after 58.2 years
0.0156 After 291 years
Explanation:
Given data:
Half-life of strontium-90 = 29.1 years
Initially present: 16g
mass present after 58.2 years =?
Mass present after 291 years =?
Solution:
Formula:
how much mass remains =1/ 2n (original mass) ……… (1)
Where “n” is the number of half lives
to find n
For 58.2 years
n = 58.2 years /29.1 years
n= 2
or 291 years
n = 291 years /29.1 years
n= 10
Put values in equation (1)
Mass after 58.2 years
mass remains =1/ 22 (16g)
mass remains =1/ 4 (16g)
mass remains = 4g
Mass after 58.2 years
mass remains =1/ 210 (16g)
mass remains =1/ 1024 (16g)
mass remains = 0.0156g