I definitly believe the answer is c. 2
Answer:
D. 613
Explanation:
I just had to answer it and that was the correct answer :)
(i didn't know it either so i was looking for help and then i came across someone who was struggling too so-)
Answer
27.7 moles
Explanation:
Data Given:
Chemical formula of Calcium carbonate = CaCO₃
no. of atoms of CaCO₃ = 8.35 x 10²⁵ atoms
moles of CaCO₃= ?
Solution
First convert number of atoms to number of molecules
As
we have 5 atoms per molecule then how many molecules will be for 8.35 x 10²⁵ atoms
So, apply unity formula
5 atoms ≅ 1 molecule of CaCO₃
8.35 x 10²⁵ atoms ≅ X molecule of CaCO₃
by doing cross multiplication
X molecule of CaCO₃ = 8.35 x 10²⁵ atoms x 1 molecule / 5 atoms
X molecule of CaCO₃ = 1.67 x 10²⁵ molecule
Formula will be used
no. of moles = no. of molecules / Avogadro's number . . . . (1)
Where
Avogadro's number = 6.022 x 10²³ molecules/mol
So,
Put values in equation 1
no. of mole = 1.67 x 10²⁵/ 6.022 x 10²³ (molecules/mol)
no. of mole = 27.7 moles
So,
moles of CaCO₃ = 27.7 moles
Answer:
Germanium.
Explanation:
In a neutral atom: the number of protons = the number of electrons.
Atomic number of a neutral atom = number of electrons = number of protons.
- Phosphorous is an element with atomic number 15 and thus contains 15 electrons and 15 protons.
- Cobalt is an element with atomic number 27 and thus contains 27 electrons and 27 protons.
- <em>Germanium is an element with atomic number 32 and thus contains 32 electrons and 32 protons.</em>
<em></em>
- Sulfur is an element with atomic number 16 and thus contains 16 electrons and 16 protons.
Answer:
a) Gold: 5, 2, 2, -1/2
b) Magnesium
: 3, 0, 0, -1/2
c) Iodine: 5, 1, 0, -1/2
d) Cadmium: 4, 2, 2, -1/2
Explanation:
To understand Chemistry in its true sense, it is necessary to know the way the electrons are arranged within the atom and also understand the how and why of the bond and reactivity. To do this, you must first know the how and why of the electronic structure. , this can be done with quantum numbers.
The quantum numbers are four and they help us to describe the place of the electrons in the vicinity of the nucleus.
