How can a scientist make sure that the results are not a mistake in an experiment?

Which of the following is not an indication of a chemical reaction? 1.) Heat is generated when two substances are combined. 2.) A solid quickly forms when two liquids are combined. 3.) A substance melts when sitting in the Sun. 4.

Enter the chemical equation for the formation of Ca (NO3) 2 (s) from its respective elements in their standard states. Express your answer as a chemical equation. Identify all of the phases in your answer.

Which statement describes the conditions in which diamonds form? A. They form as water evaporates on the shore of any body of water, B. They form deep underground, in most regions of Earth, c.

In the balanced equation 4Fe + 3O2 = 2Fe2O3 how many atoms of iron (Fe) are reacting with every three molecules of oxygen (O2) ?

1.) Molecules involved in a chemical reaction must collide to react. What is this concept called?. a. collision theory b. entropy ... c. enthalpy ... d. reaction rate ... 2.) Which of the following equations is used to describe reaction rates?. a.

The masses of reactants is always greater than the masses of the products in a chemical reaction, because the products are combined together. TRUE FALSE

Which is a characteristic of a solution1. its particles scatter light2. ita particles are evenly distributed 3. its particles settle out 4. it has large suspended particles

Why might the increase of noise in natural areas be a problem, according to scientists studying wildlife? Support your answer with at least two details from the text.

What changes nitrogen gas in the air to nitrogen compounds that fall to the ground

How much time does it take a person to walk 12 km north at a velocity of 6.5 km/h