How many moles of calcium (Ca) atoms are there in 77.4 g of Ca?

What is a solution? a solid dissolved in a gas a solute and a solvent a liquid dissolved in a gas an amalgam of solids, liquids, and gases

What is the pressure that must be exerted on 300 ML of gas which has been collected at STP so that it may be confined to a volume of 190 ML? Temperature is kept constant.

Is the reaction mg²⁺ (aq) + h₂o (l) → mgo (s) + 2h⁺ (aq) endothermic or exothermic?

Which statement about schrodingers theory of the atomic model is true?

Taylor mixed two liquids together in a beaker. The beaker quickly heated up. What does this indicate about the reaction that took place in the beaker?

Is phosphorous an atom, element, or compound

A noble gas consists of three isotopes of masses of 19.99 amu, 20.99 amu, and 21.99 amu. the relative abundances of these isotopes are 90.92%, 0.257%, and 8.82% respectively. what is the average atomic mass of this noble gas? what noble gas is this?

Adding iron filings to sand

Which of the following sets of empirícal formula, molar mass, and molecular formula is correct?

Hexane and hexene are hydrocarbon compounds from different homologous series. the combustion of these two compounds produce different amount of soot. explain the difference based on the percentage of carbon by mass.