What element has 8 valence electrons

A certain mass of gas in a 2.25L container has a pressure of 164 kPa. what will the new pressure be if the volume of the container is reduced to 1.50 L and the temperature stays constant?

what is the isotope notation for an element with a mass number of 49, and 21 protons? what is the atomic number and number of neutrons, as well?

Which of the following types of energy does an object have because of its position?

What is the volume of 1.56 kg of a compound whose molar mass is 81.86 g/mole and whose density is 41.2 g/ml?

516 mL of a 3.82 M sodium sulfate (Na2SO4) solution is diluted ith. 875 L of water. What is the new concentration in molarity?

Which two properties are used to define matter? has mass and conducts heat has buoyancy and volume has mass and takes up space conducts energy and has characteristic properties

Calculate the energy if 48.7 g of Al reacts in the following reaction. (Al = 26.98 g/mol) Fe2O3 (s) + 2 Al (s) →Al2O3 (s) + 2Fe (s) ∆Hrxn = - 852 kJ.

Which type of wave has a wave perpendicular to the disturbance? Surface Longitudinal Mechanical Tranverse

Caffeine's molecular formula is c8h10n4o2. the molar mass of caffeine is 194g/mol. what is the percentage of carbon in caffeine

Which will evaporate more quickly: 55 mLmL of water in a beaker with a diameter of 4.5 cmcm, or 55 mLmL of water in a dish with a diameter of 12 cmcm?