Answer: The mole allows people to calculate the number of middle schoolers entities (usually atoms or molecules. Isabella's number is an absolute number: there are 6.022 × 1023 middle schoolers entities is in 1 mole. This can also be written as 6.022 × 1023 mol-1.
Explanation: I hope that helped !!
Answer: D=8.27 g/cm³
Explanation:
Density is mass/volume. Mass is in grams and volume is in liters. In this case, the problem wants our volume to be in cm³. All we need to do is to make some conversions to convert kg/m³ to g/cm³.

With this equation, the m³ and kg cancel out, and we are left with g/cm³.
D=8.27 g/cm³
According to the law of conservation of mass, the mass of reactants will be equal to the mass of the products. The mass of products and reactants will only differ during a nuckear reaction
Changing of the physical state of water is not a nuclear reaction. So becoz of that the mass will remain constant without any change.
D milk turning sour
the other options are physical changes