If you roast a marshmallow is it a chemical or physical change

Two objects with identical charges are placed a distance d from one another. The force between the objects is measured as F. If the distance between the objects is halved, what will the force between them be?

What happens to the atomic number of an atom when the number of neutrons in the nucleus of that atom increases?

Based on its position in the periodic table, which of the following elements is most reactive, helium, carbon, argon, or fluorine

How are electrons arranged in an atom

It requires 350 joules to raise a certain amount of a substance from 10.0°C to 30.0° c. The specific heat of the substance is 1.2 J/g° c. What is the mass?

Water is a compound. O A. True B. False

How do air quality scientists ensure the air is cleaned? What steps do they take?

Is a mirrors surface opaque or transparent or translucent?

Sound waves can combine to become bigger or smaller true or false

Archimedes supposedly was asked to determine whether a crown made for the king consisted of pure gold (density of gold is 19.3 * 103 kg/m3). According to legend, he solved this problem by weighing the crown first in air and then in water.