Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements or simpler compounds.
Ex: cutting a paper, gaining weight, cutting hair
Answer:
The compound with the correct formula is;
A. MNO₃
Explanation:
The number of oxidation states in the metal, M = One oxidation state
The formula of the compound formed by the metal, M = MHCO₃
We note that the ion HCO₃⁻, known as hydrogen carbonate has an oxidation number of -1
Similarly nitrate, NO₃⁻ has an oxidation number of -1, therefore, the metal M can form similar compound formed with HCO₃⁻ with nitrate, and we have;
The possible compounds formed by the metal 'M' includes MHCO₃ and MNO₃.
In order to calculate the molar mass of the protein, we may manipulate the ideal gas equation:
PV = nRT, where n is the number of moles. We also know that:
n = m / Mr, where m is mass and Mr is molecular weight
Thus,
Mr = (mRT)/(PV)
Here, the mass is in grams, the temperature is in Kelvin, the pressure is in atm and the volume is in liters, so the molar gas constant is 0.082057.
Mr = (3.6 * 0.082057 * (27 + 273)) / (0.0203 * 0.2)
Mr = 21,828 g/mol
Thus, the Mr of the protein is 2.18 x 10⁴ g/mol
