The answer is b
Protons and neutrons are both in the nucleus
Electrons are outside the nucleus
Answer:
gamma ray
Explanation:
Gamma emission results in the release of energy without any apparent change in mass or nuclear charge.
Properties of Gamma radiations:
Gamma radiations are high energy radiations having no mass.
These radiations are travel at the speed of light.
Gamma radiations can penetrate into the many materials.
These radiations are also used to treat the cancer.
Lead is used for the protection against gamma radiations because of its high molecular density.
The lead apron are used by the person when treated with gamma radiations.
Lead shields are also used in the wall, windows and doors of the room where gamma radiations are treated, in-order to protect the surroundings.
Answer:
860 J / mol
Explanation:
Enthalpy = Energy / no. of moles
no. of moles = mass / molar mass
Take the atomic mass of H = 1.0,
molar mass of H2 = 1.0 x 2
= 2.0
no. of moles of H2 = 9.00/2
= 4.5 mol
Hence,
Enthalpy = 3870 / 4.5
=860 J / mol
To bond with another atom
Answer:
19.4 g of alum, will be its theoretical yield
Explanation:
The reaction is:
2 Al + 2 KOH + 4 H₂SO₄ + 22H₂O → 3H₂ + 2KAl(SO₄)₂•12H₂O
Let's determine the amount of acid.
M are the moles contained in 1 L of solution or it can be mmoles that are contained in 1 mL of solution
M = mmol /mL
M . mL = mmol
We replace: 8.3 mL . 9.9 M = 82.17 mmoles
We convert to moles: 82.17 mmol . 1 mol / 1000mmol = 0.082 moles
Ratio is 4:2
4 moles of sulfuric acid can make 2 moles of alum
By the way, 0.082 moles of acid may produce ( 0.082 . 2) /4 = 0.041085 moles.
We convert moles to mass:
Molar mass of alum is: 473.52 g/mol.
0.041085 moles . 473.52 g/mol = 19.4 g