A sample that weighs 107.75 g is a mixture of 30% helium atoms and 70% krypton atoms. How many particles are present in the sample?

What is the molarity of a solution containing 2 moles of HCl (hydrochloric acid) in 3 liters of water?

Looking across period 4 of the periodic table, potassium (atomic number 19) is followed by calcium (atomic number 20), which is followed by scandium (atomic number 21). Which element should have the largest atomic radius?

Gravity is matter because it does not have mass and volume.

What did Aristotle believe? O A. That the scientific method should be used to test ideas OB. That all matter was composed of earth, fire, water, and air O c. That matter did not exist in the physical world O D.

What did Ernest Rutherford's gold foil experiment demonstrate about an atom? Each atom is composed of electrons and positive material. The mass of the atom is evenly spread throughout the atom. Neutrons are located in the center of the atom.

How does phosphorus enter the human body?

When a reaction occurs between atoms with ground state electron configuration 1s2 2s1 and 1s2 2s2 2p5 the predominant type of bond formed is

How does heat transfer takes place between any two systems?

Hydrate name of CaCl2 * 8 H2O

Calculate the heat evolved from a mixture of 14.1 l of sulfure dioxide