In physical changes, the atoms or molecules that compose the matter do not change their identity, even though the matter may change its appearance.

a. True

b. False

A tank of methane gas contains 2.8 m³ of the gas at 20°C. The tank has a pressure-release valve that releases gas into a secondary tank that will hold 0?2m³ of gas if the pressure rises.

Hydrogen Peroxide, H2O2, in the presence of a catalyst decomposes into water and oxygen gas. How many L of O2 at STP are produced from the decomposition of 34.0g of H2O2? A.) 1.00B.) 5.60C.) 11.2D.) 22.4

What is called what a scientist personal opinion affects the way experimental results are reported? A. Bias B. Classifying C. Inductive reasoning D. Procedure

Calculate the mass of products obtained when 20 g of methane undergoes combustion in the presence of 16 g of oxygen?

The first system of classification of organisms was developed by? 1. Darwin 2. Linnaeus 3. Watson 4. Mendel

Which of the following is true about a redox reaction? In a redox reaction, an electron is lost by the reducing agent. In a redox reaction an electron is lost by the oxidizing agent.

Is the equation above balanced? How do you know? Mg + 2HCl → MgCl2 + H2

What characteristics do atoms of carbon-12, carbon-13, and carbon-14 have in common?

Which of the following changes would decrease the rate at which a solid solute dissolves in a liquid solvent? A. Decreasing pressure B. Decreasing surface area C. Increasing rate of stirring D. Increasing temperature

Helium, neon, and argon are examples of A) metals B) metalloids C) noble gases D) transitional metals