Which of the following could be classified as matter? Check all of the boxes that apply. desk water idea cloud helium dream

Which statement is true of all matter

Why is it important to conduct more than one trial during a scientific investigation?

A 75 g piece of gold (Au) at 1000 K is dropped into 200 g of H2O at 300K in an insulatedcontainer at 1 bar. Calculate the temperature of the system once the equilibrium has beenreached.

What is the partial pressure of hydrogen in a gas mixture containing hydrogen and oxygen if the total pressure is 1500 mmHg and the partial pressure of oxygen is 455mmHg

Convert 27 moles of O into atoms 4.5 x 10^ - 23 atoms 1.6 x 10^25 atoms 2.2 x 10^22 atoms 1.7 atoms

Suppose that you measure a pen to be 10.5 cm long. Convert this to meters.

How are amounts of hydrogen and oxygen gas made from the electrolytic decomposition of water related to the chemical formula of water?

Hydrogen peroxide decomposes to water and oxygen at constant pressure by the following reaction: 2H2O2 (l) → 2H2O (l) + O2 (g) ΔH = - 196 kJ Calculate the value of q (kJ) in this exothermic reaction when 3.

What is the concentration of hydronium in each of the following cases: [OH-] = 10-12 M? [OH-] = 10-2 M?

Which statement best explains why elements are matter? An element is a physical substance that has mass and takes up space. Elements are pure substances that cannot be divided chemically. Each element is a pure substance composed of one type of atom.