When two atoms of Hydrogen combine together, or fuse, they make an atom of Helium.
Answer:
Quartz.
Explanation:
According to the characteristics given in the question the mineral must surely be Quartz.
Quartz does not react with hydrochloric acid.
Its is pink in color and has anon metallic luster. It has a specific gravity of 2.65. Quartz is continuous framework of SiO4 , with each oxygen being shared with two tetrahedra, giving an overall chemical formula of SiO2.
Answer : The expected coordination number of NaBr is, 6.
Explanation :
Cation-anion radius ratio : It is defined as the ratio of the ionic radius of the cation to the ionic radius of the anion in a cation-anion compound.
This is represented by,

When the radius ratio is greater than 0.155, then the compound will be stable.
Now we have to determine the radius ration for NaBr.
Given:
Radius of cation,
= 102 pm
Radius of cation,
= 196 pm

As per question, the radius of cation-anion ratio is between 0.414-0.732. So, the coordination number of NaBr will be, 6.
The relation between radius ratio and coordination number are shown below.
Therefore, the expected coordination number of NaBr is, 6.
Answer is: <span>b.20.0 L </span><span>liters of ammonia are needed to react completely.
</span>V(NO) = 30 L.
n(NO) = V(NO) ÷ Vm.
n(NO) = 30 L ÷ 22,4 L/mol.
n(NO) = 1,34 mol.
From chemical reaction: n(NO) : n(NH₃) = 6 : 4 (3 : 2).
n(NH₃) = 4 · 1,34 mol ÷ 6.
n(NH₃) = 0,892 mol.
V(NH₃) = 0,892 mol · 22,4 L/mol.
V(NH₃) = 20 L.
<span>The amount of
protons is equal to the number of electrons of a chemical element. The atomic
number of an element also determines the number of the protons it contains.
The number of protons is also the same number of electrons. Protons are positively charged, electrons are
negatively charged. To get the number of neutrons, all you need is to deduct
the number of the atomic mass or mass number from the atomic number. Potassium has 19
protons, therefore has 19 electrons as well. The atomic mass of Potassium is
39. So, the number of neutrons Potassium has is 20. </span>
Potassium
Atomic
number: 19
Protons: 19
Electrons: 19
Atomic Mass:
39
Neutron: 20
Nitrogen
Atomic
number: 7
Protons: 7
Electrons: 7
Atomic Mass:
14.007
Neutrons: 7
Oxygen
Atomic
Number: 8
Protons: 8
Electrons: 8
Atomic Mass:
15.99
Neutrons: 8