Is heating sulfur and copper a physical or chemical change?

Describe at least two advantages and two disadvantages of using coal as a source of energy

Match the vocabulary word with its definition. Match the items in the left column to the items in the right column. 1. A charged atom or particle valence electrons 2.

How many neutrons does an element have if its atomic number is 47 and its mass number is 150?

Which of the following statements of kinetic molecular theory explains the compressibility of gases as compared to liquids and solids? Gases are made of molecules which are relatively far apart. The molecules are in motion at high speeds.

A cast fossil is formed when A) an organism leaves an impression in rock B) an organism leaves a footprint C) minerals fill in an impression left by an organism D) when the remains of a living thing are preserved and turned into rock

Which usually has a higher temperature? A city or the areas around the city?

Toluene and pyridine form ideal solutions. Consider a solution of toluene and pyridine prepared at 25°C. Assuming that the mole fractions of toluene and pyridine in the vapor phase are equal, calculate the composition of the solution.

Formula for water what does the lack of a subscript after those O indicate

Why do the chemical properties cycle through each period? Every eighth element starting with hydrogen restarts the transition from metal to inert gas. Elements with atomic numbers which are multiples of eight start a new period.

Which statement correctly describes the Ka of a weak acid? The Ka is large, and the equilibrium favors products. The Ka is large, and the equilibrium favors reactants. The Ka is small, and the equilibrium favors products.