Which is an example of a chemical reaction? paper folded into tiny pieces paper burned and turned into smoke paper soaked in water paper shredded and turned into pulp

Question 17 The atomic mass of an element is determined by the number of protons and neutrons contained in the nucleus. changes after each reaction. equals the number of protons plus the number of electrons. depends on the number of electrons in the outermost shell. equals the number of neutrons. Question 18 Isotopes are: charged ions. locations of electrons in atoms. atoms of the same element that differ in the number of neutrons. atoms of the same element that differ in the number of electrons. Question 19 What are charged particles that form when electrons are transferred from one atom to another? Atoms Elements Molecules lons Question 20 2 pts 2 pts 2 pts

What type of reaction takes place when one atom or molecule gains electrons and another loses them? Redox Double Replacement Displacement Combination

Question 44 Text to Speech Once the skeleton equation is written, what do we need to do to it to make it a complete chemical equation? Determine the molar mass of the materials present Balance the number of atoms from the reactants to the products Add the names of the materials Remove the ions that do not take part in the reaction

What is chemistry? A. The scientific study of matter B. The study of living things C. The study of how matter and energy interact D. The study of changing ideas

Which of the following pairs of elements lists both a nonmetal and a metal Cr and Na Se and Mg Kand Ca Fand N

In the reaction $C_{3}H_{6}+HBr\rightarrow C_{3}H_{7}Br$ $C_{3}H_{6}$ and HBr are both reactants $C_{3}H_{7}Br$ is the only reactant $C_{3}H_{7}Br$ is the only reactant $C_{3}H_{6}$ and HBr are both products

What is the formula for copper(III) sulfite? $Cu_{2}SO_{3}$ $CuSO_{3}$ $Cu(SO_{3})_{2}$ $Cu_{2}(SO_{3})_{2}$

How many ${}^{1}H$ NMR signals does 2-chloro -3-methyl-2-butene exhibit? Assume both geminal methy!show as chemically equivalent in the NMR 1 2 2 3 4 5

Which is the pH range for bases? 4 to 8 0 to7 9 to 14 7 to 14

0.349 g of $CaCO_{3}$ was precipitated from a reaction of an unknown mixture containing $Na_{2}CO_{3}$ with excess $Ca(NO_{3})_{2}$ $Na_{2}CO_{3(aq)}+Ca(NO_{3})_{2(aq)}\rightarrow CaCO_{3(s)}+2NaNO_{3(aq)}$ How many grams of $Na^{+}$ ions were in the unknown mixture containing $Na_{2}CO_{3}$ Answer: $\square $