CHEM121

The mass of an object is a measure of the amount of matter in the object The melting of ice to liquid water is correctly classified as a physical change Which of the following is a chemical property of matter flammability Which of the following substances are composed of heteroatomic molecules water What is a heteroatomic molecule molecules that do not have the same atoms making up the molecule. Table salt, NaCl is best classified as a compound What is a compound 2 or more elements...

How many nonbonding pairs of electrons are present in the lewis dot structure of a molecule with formula AX2? A has 4 valence electrons while each X has 7. 6 What is the shape of a molecule which has the formula AX3? A has 6 valence electrons as does each X. trigonal planar What is the shape of a molecule which has the formula AX2-1? A has 3 valence electrons while each X has 6. linear What is the shape of a molecule which has the formula AX3? A has 5 valence electrons while X has 7. trig...

An object with a mass of 0.255 kg and density of 2.89 g/cm3 measures 34 mm in length and 46 mm in width. What is the height of the object? 5.6 cm A 0.150 kg metallic block measures 25.0 mm in length, 43.0 mm in width, and 19 .0 mm in height. What is the density of the metallic block in g/cm3? 7.34 g/cm3 How would you determine the density of an irregular object? D = m/v, so measure the mass of the object using a balance. Then to find volume, fill a graduated cylinder with a known amount of ...

Which of the following represents oxidation? a. 2H+ + 2e- ->H2 b. F2 + 2e- -> 2F- c. Na -> Na+ + e- d. Mg2+ + 2e- -> Mg e. Ni2+ + 2e- -> Ni c. Which element is reduced in the reaction below? Na2SO4 + 4C -> Na2S + 4CO S What is the oxidation number of P in (PO4)3-? +5 What is the molarity of a solution that results when 21.3g of (NH4)3PO4 is dissolved in water and diluted to exactly 250.0ml? 0.572 M Which is not an electrolyte? a. H20 b. NH4Cl c. KI d. CuS a. ...

What is the meaning of the two (2) in ethyl alcohol C2H5OH? a. all alcohol molecules contain two carbon atoms b. there are two carbon atoms per molecule of ethyl alcohol c. carbon is diatomic d. all of these b. there are two carbon atoms per molecules Which of the following uses the unit "u" or "amu"? a. atomic weights of atoms b. relative masses of atoms c. molecular weights of molecules d. more than one response is correct d. more than one response is correct. Determine...

what does the letters in RAMP stand for R=Recognize hazards A=Assess risks M=Minimize risks P=Prepare for emergencies Personal factors attitude, beliefs, personality, skills behavior factors safe and risky practices Environmental factors location, equipment, procedures many accidents in labs are cause by poor house keeping fire alarms should be pulled when? when there is a need to leave the building whether there is a fire or not. What should you do after pulling the fire alarm c...

compressibility measure of how much the volume of matter decreases under pressure Why are gases easier to compress than solids or liquids are? gases are easily compressed because the space between the particles in a gas what are 3 factors that affect gas pressure? 1. amount of gas 2. temperature 3. volume Boyle's Law states that for a given mass of gas at constant temperature, the volume of the gas varies inversely with pressure. P₁ x V₁ = P₂ x V₂ Charles's Law states th...

Four families of hydrocarbons alkanes, alkenes, alkynes, aromatics Alkanes Hydrocarbons that contain only single bonds Alkenes Hydrocarbons with one or more carbon-carbon double bonds Alkynes a carbon compound with a carbon-carbon triple bond. Aromatics A carbon compound with a benzene ring Pentane 5 carbons and C-C single bonds Butene Contains 4 carbon bonds and a C=C double bond Cyclohexene 6 carbons, a ring and a C=C double bond octyne 8 carbons and a C-C triple bond Saturat...

three examples of nuclear reactions energy generation by the sun the destructive hydrogen bomb atomic bomb explosions. two basic types of nuclear reactions Radioactive decay Transmutation Transmutation Nuclear bombardment Causes nucleus rearranges to give rise to another new nucleus Radioactive decay Spontaneous breakdown into a stable isotope of the same element or another element Write nuclear symbols for chlorine-35 35CL17 Write the nuclear symbols for bromine-79 79Br35 Write ...