In the nucleus of an atom, there are 18 protons and 20 neutrons. What are the atomic number and mass number of this isotope?

Which is heavier a pound or kilogram? By how much

Underground igneous rock bodies are called

My last question before this doesn't need to be answered anymore

An object such as a hammer weights less on the moon than on earth. this is because the moon has a

A charge of 9.0 x 10-5C is placed in an electric field with a strength of 4.0 x 104 N. What is the electrical force acting on the charge?

Comparing and contrasting ionic and covalent bonds?

Elevation above sea level is called

The train traveled 500 kilometers north to Odessa in 2 hours. What's the train's speed? What is the velocity?

Are microwaves and radio waves faster or slower than other types of electromagnetic energy?

If you dive under-water, you notice an uncomfortable pressure on your eardrums due to the increased pressure. The human eardrum has an area of about 70 mm2 (7*10-5m2), and it can sustain a force of about 7 N without rupturing.