How is ice-cream melting a physical change?

Be sure to answer all parts. A sample of nitrogen gas expands in volume from 1.4 to 5.8 L at constant temperature. Calculate the work done in joules if the gas expands (a) against a vacuum: J (b) against a constant pressure of 0.

Benzene has the empirical formula and an empirical formula weight of 13.0 amu. If the molecular weight is 78.0 amu, what is the molecular formula? (Enter the elements in the order: C, H.)

Which of the following is a type of chemical used in fertilizer? A. hydrate B. hydrite C. nitrate D. phosphate

How many moles of silver chloride are produced from 15.0 mol of silver nitrate?

What is one group of people or animals that are impacted by ocean acidification?

Hemoglobin, a protein in red blood cells, carries o2 from the lungs to the body's cells. iron (as ferrous ion, fe2+) makes up 0.33 mass % of hemoglobin. if the molar mass of hemoglobin is 6.8 Ã 104 g/mol, how many fe2 + ions are in one molecule?

What could you predict about a methane molecule that would most likely be made by using both the quantum model of the atom and John Dalton's model?

What is the molar mass of an unknown hydrocarbon whose density is measured to be 1.97 g/l at stp?

Which is an example of flow of heat through conduction

Which of the following is an extensive physical property of matter? volume viscosity odor density