How do atomic mass and atomic number change across and dow the periodic table of elements?

Consider an atom of sodium with an atomic number of 11 and an atomic weight of 23. how many neutrons are in this atom

What is the formula to mechanical energy?

In an experiment, 50 g of each material were placed in a calorimeter with the same starting water volume and temperature. Which is the best interpretation of the chart? Lead has the highest specific heat of the four materials shown.

Why molecules of oxygen must have an even number of water

17kg of aluminium was produced from 51kg of aluminium oxide (Al2O3) by electrolysis. What was the percentage yield?

The absence of which cell structure would indicate a cell is prokaryotic?

When 0.880 g of an organic compound containing carbon, hydrogen and oxygen is burned completely in oxygen, 1.760 g of co2 and 0.720 g h2 o are produced. what is the empirical formula of the compound?

In ammonium chloride salt (nh4cl) the anion is a single chloride ion, cl. what is the cation of nh4cl

What does copper II sulfate do to the enzyme activity?

In a closed system, if a gas is transported to a container with double the volume of the previous container, gas was held in, What is the gases' new volume?