What element is mostly used in magnets, gold or cobalt?

What mass is needed for 5000 moles of iron.

A handbook gives the density of calcium as 1.54 g/cm3. based on lab measurements, what is the percentage error of a density calculation of 1.25 g/cm3? 37. what is the percentage error of a length measurement of 0.229 cm if the correct value is 0.

Why don't noble gases bond?

Why does magnesium fluoride conducts electricity when molten or in aqueous solution?

Elizabeth is pushing against a wall as she stretches before exercising as shown below. The wall pushes back against Elizabeth's hands with the same force in the opposite direction. Which of Newton's laws does this best demonstrate? A.

Four moles of hydrogen chloride (HCl) gas react with one mole of oxygen (O2) gas to produce two moles of chlorine gas (Cl2) and two moles of water gas (H2O).

The density of rubbing alcohol is 0.785g/mL at 25 Celsius. Calculate the mass of 15.0 mL of the rubbing alcohol.

Is the universe an isolated system?

1000ml of a gas is cooled from 500 K to 250 K, what is it's final volume? A. 250 ml B. 1000 ml C. 500 ml D. 750 ml E. 2000 ml

A reacton has a theoretical yield of 22.8g. When the reaction was carried out, 15.1g of the product was obtained. What is the percent yield?