A variable is something that can never be changed in an experiment.

False

True

The two esters below are synthesized from the starting material below. identify and draw the neutral reagent that is missing.

What can be added to an atom to cause a nonvalence electron in the atom to temporarily become a valence electron? energy mass neutrons electrons

Which mixture can be separated through filtration because one the substances is insoluble in water? Answers: * NaChO and Pb (ClO) * Na SO and SrSO * NaNO and Pb (NO) * NaC H O and Pb (C H O)

Explain why indicators are useful for measuring pH

As a chemical reaction occurs, the thermometer in the container records an increase in temperature. What is true of the reaction? The reaction is endothermic because heat was taken in by the reaction.

Certain types of organisms such as fireflies and anglerfish can produce light through chemical reactions in a process called bioluminescence.

Water drops forming on the outside of a cold glass is an example of which phase change

A balloon containing 0.0400 mol of a gas with a volume of 500 mL was expanded to 1.00 L. Answer the questions and round answers to nearest hundredth place. Which equation should you use to find the amount of gas added?

Can quadrilateral RSTU be a parallelogram

Four moles of hydrogen chloride (HCl) gas react with one mole of oxygen (O2) gas to produce two moles of chlorine gas (Cl2) and two moles of water gas (H2O).