Oxygen<span> is a </span>chemical element<span> having a symbol </span>O<span> and having an </span>atomic number<span> 8.
Oxygen is a pure substance , and it is not a mixture or solution, Niether it is a compound ... Instead , it forms chemical compounds by reacting with other elements.
So , according to above explanation ,
A. A pure substance , is the correct answer.</span>
Answer:
Condensation occurs when a gas changes into a liquid.
Explanation:
Condensation is when a gas becomes a liquid. It happens when a gas, like water vapor, cools down. Matter can exist in three different states: solid, liquid or gas.
Answer:
Explanation:
Using freezing point depression formula,
ΔTemp.f = Kf * b * i
Where,
ΔTemp.f = temp.f(pure solvent) - temp.f(solution)
b = molality
i = van't Hoff factor
Kf = cryoscopic constant
= 1.86°C/m for water
= (0 - (-5.58))/1.86
= 3.00 mol/kg
Assume 1 kg of water(solvent)
= (3.00 x 1)
= 3.00 mol.
Answer:
31.78 grams
25.55%
Explanation:
The balanced reaction for ammonium chloride with calcium oxide will be:
2NH4Cl + Ca(OH)2 ---> CaCl2 + 2NH3 + 2H2O
The molecular weight for ammonium chloride(NH4Cl ) is 53.49g/mol, while the molecular weight for ammonium(NH3) is 17g/mol. The number of theoretical yield of ammonia from 100g of ammonium chloride will be:
100g / (53.49g/mol) * 2/2 * 17g/mol= 31.78 grams
If the actual yield is 8.12g, the percent yield will be: 8.12g/31.78g * 100% =25.55%
Answer:
beta particle
Explanation:
Explanation:
Alpha beta and gamma radiations are the examples of ionizing radiations. When an atom is an excited state and having high energy, the atom is in unstable state. The excess of energy is released by the atom to get the stability. The released energy is in the form of radiations which may include alpha, beta, gamma, X-ray etc.
¹⁴₆C → ¹⁴₇N + ⁰₋₁e
The beta radiations are emitted in this reaction. The one electron is ejected and neutron is converted into proton.
Beta radiations:
Beta radiations are result from the beta decay in which electron is ejected. The neutron inside of the nucleus converted into the proton an thus emit the electron which is called β particle.
The mass of beta particle is smaller than the alpha particles.
They can travel in air in few meter distance.
These radiations can penetrate into the human skin.
The sheet of aluminium is used to block the beta radiations