Answer:
In a chemical reaction, there is a change in the composition of the substances in question; in a physical change there is a difference in the appearance, smell, or simple display of a sample of matter without a change in composition. Although we call them physical "reactions," no reaction is actually occurring.
The standard ambient temperature and pressure are
Temperature =298 K
Pressure = 1atm
The density of gas is 1.5328 g/L
density = mass of gas per unit volume
the ideal gas equation is
PV = nRT
P = pressure = 1 atm
V = volume
n = moles
R= gas constant = 0.0821 Latm/mol K
T = 298 K
moles = mass / molar mass
so we can write
n/V = density / molar mass
Putting values



Thus molar mass of gas is 37.50g/mol
A spring scale is a type of weighing scale, it works because it uses a spring that is proportional to the distance that the spring is from its resting position.
In viewing a chemical equation,we <span>determine the ratios that relate reactants and products </span>from the coefficients of the reactants and products .