What is concentration in science

Which of the following is a heterogeneous mixture Air Salt water Steel Soil I think it's soil but I'm not positive

A volume of 18.0 l contains a mixture of 0.250 mole n2, 0.250 mole o2, and an unknown quantity of he. the temperature of the mixture is 0 ∘c, and the total pressure is 1.00 atm. how many grams of helium are present in the gas mixture?

A flask contains 4.4g of carbon dioxide gas. calculate how many moles CO2 gas does it contains?

Aquifers and wells are two major sources of a. groundwater c. rivers b. lakes d. none of the above

What is the electronic geometry of h2o? enter the electronic geometry of the molecule?

A solid substance turns into a liquid. Which best describes this change?

List two things you know about nonrenewable energy

Does a mole of hydrogen have the same mass as a mole of oxygen? explain your answer.

A 0.500-L sample of H₂SO₄ solution was analyzed by taking a 100.0mL aliquot and adding mL of. After the reaction occurred, an excess of ions remained in the solution. The excess base required mL of for neutralization.

Ammonia can be prepared by the reaction of magnesium nitride with water. The products are ammonia and magnesium hydroxide. Write and balance the equation.