pure substance x is a green powder. when heated, it gives off a gas and changes to a black powder. is substance x an element or a compound? give reasons

What properties applies to solids but not to liquids or gases?

Which of the following lists included the major types of mountains? A. Folded, fault-block volcanic. B. Folded, tensions compressional. C. Downwraped, compressional, fault-block. D. None of the above

Looking at the structure of caffeine, explain why it is very soluble in a non-polar solvent and a little soluble in water.

How many atoms are in 163 g of calcium?

What is the voltage of a galvanic cell made with magnesium and gold

How many elements are found in the following chemical equation? K + Cl → KCl A. 1 B. 2 C. 3 D. 0

How many liters of 0.85 M HCl solution would react completely with 3.5 moles Ca (OH) 2?

The specific heat of aluminum is 0.897 J/g•°C. Which equation would you use to calculate the amount of heat needed to raise the temperature of 0.75 g of aluminum from 7°C to 29°C? A. Q = 0.75 g x 0.897 J/g•°C x 22°C B. Q = 0.75 g x 0.

Carbon dating advisable for measuring materials ages for a few years, thousands of years, millions of years

What is the pH of a solution with [H+] = 7.0 x 10^-2?