Which of the following statements describe the physical properties of a penny?

A) It is smooth and shiny

B) It is light and thin

C) It turns brown in water

D) It gets hot in the sun

There may be more than one answer

helium gas in a 2.00 L cylinder is under 1.12 atm pressure. At 36.5°C that same gas sample has a pressure of 2.56 atm. What was the initial temperature of the gas in the cylinder?

How many electrons does a lithium atom give off when it reacts

Which of the following statements best describes the Aufbau principle?

Which type of substance can conduct electricity in the liquid phase but not in the solid phase and why? 1) ionic compound 2) metallic compound 3) nonmetallic compound 4) molecular compound

A Chemist prepares a solution of sodium nitrate (NaNO3) by measuring out 122. g of sodium nitrate into 250. mL volumetric flask and filling the flask to the mark with water.

Calculate the density of a rectangular solid that has a mass of 25.71 g, and its dimensions are 2.3 x 4.01 x 1.82 cm.

When the metal sample reacts with acid, the gas evolved will be collected over water; the gas is said to be "wet".

Solid iron (II) sulfide reacts with aqueous hydrochloric acid HCl to produce hydrogen sulfide gas H2S and aqueous iron (II) chloride.

How are mixtures compounds and elements alike?

The percentage of carbon dioxide in the atmosphere has increased in the last century and is a concern for the environment as it increases the greenhouse effect. Give one possible explanation for the increase of carbon dioxide in the atmosphere