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

Which scientist provided a foundation for John Dalton's work on the atomic structure? A. Robert Millikan B. Joseph Proust C. Ernest Rutherford D. J. J. Thomson

Enzyme A and Enzyme B both catalyze the same reaction. If Enzyme A has a larger turnover number than Enzyme B, then which enzyme, if either, has a higher catalytic efficiency? Enzyme B is more efficient because it's turnover number is smaller.

Which is a type of protein?

When we boiling the ice, why after about 15 minutes the temperature of it doesn't change anymore? (answer by temperature/molecules/phase change)

A hot air balloon is filled with of an ideal gas on a cool morning (The air is heated to What is the volume of the air in the balloon after it is heated? Assume that none of the gas escapes from the balloon.

Calculate the number of particles (atoms or molecules) of the following: 1. How many molecules are there in 24 grams of FeF3? 2. How many molecules are there in 450 grams of Na2SO4? 3. How many grams are there in 2.3 x 1024 atoms of silver?

Write a balanced equation for the decomposition reaction described, using the smallest possible integer coefficients. When calcium carbonate decomposes, calcium oxide and carbon dioxide are formed.

What is the atomic number of magnesium?

Explain how earth plates and lithosphere are related

What is the name for the Fe2 + cation? Iron ion Iron (II) ion Ironide Ferride ion