Answer:
321.6 g/Mol
Explanation:
mass of solvent in kilograms = 90g/1000 = 0.09 Kg
Given that;
ΔTf = Kf . m . i
Where;
Kf = freezing point constant = 4.25 °C/Kg mol
m = molality of the solution
i = Van't Hoff factor = 1 (since the substance is molecular)
ΔTf = freezing point of pure solvent - freezing point of solution
freezing point of pure solvent = 3 °C
ΔTf = 3 °C - 2.1 °C
ΔTf = 0.9 °C
0.9= 4.25 * 6.13/M/0.09 * 1
0.9= 26.0525/M * 1/0.09
0.9 = 26.0525/0.09 M
0.9 * 0.09M = 26.0525
M = 26.0525/0.9 * 0.09
M= 321.6 g/Mol
Explanation:
A property which causes change in chemical composition of a substance is known as a chemical property. For example, reactivity, toxicity, combustion etc.
Whereas a property which causes no change in chemical composition of a substance is known as a physical property. For example, mass, volume, density etc.
Sodium is a very reactive metal and it reacts readily with oxygen, water etc. So, when sodium is added to water then occurrence of an orange flame represents its reactivity.
Thus, based on given observation it can be concluded that chemical reaction takes place when sodium is added to water.
Answer:
The molar mass of the gas is 44.19 g/mol
Explanation:
Amount of sample of gas = m = 13.5 g
Volume occupied by the gas = V = 5.10 L
Pressure of the gas = P = 149.83 KPa
1 KPa = 0.00986 atm
P = 
Assuming M g/mol to be the molar mass of the gas
Assuming the gas is behaving as an ideal gas

The molar mass of gas is 44.19 g/mol
Answer:
Answer to A. helium, neon, argon, krypton, xenon, and radon, B. Elemental hydrogen (H, element 1), nitrogen (N, element 7), oxygen (O, element 8), fluorine (F, element 9), and chlorine (Cl, element 17) are all gases at room temperature, and are found as diatomic molecules (H2, N2, O2, F2, Cl2). C. Elements Compounds
Ar (argon) HBr (hydrogen bromide) C 3H 8 (propane)
Kr (krypton) HI (hydrogen iodide) C 4H 10 (butane)
Xe (xenon) HCN (hydrogen cyanide)* CO (carbon monoxide)
Rn (radon) H 2S (hydrogen sulfide) CO 2 (carbon dioxide)
Explanation: