Chemistry Lab

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Which compounds do you think contain a carboxylic acid group based on this test? A)A and E B)All of them C)A and C D)Only E

A)A and E

Based on what you have seen, which is the best definition for an acid? A)Acids donate protons in aqueous solutions B)Acids accept protons from water molecules C)Acids split into two molecules in aqueous solution D)Acids remove protons from each water molecule

A)Acids donate protons in aqueous solutions

Remember the Bronsted-Lowry definition of acids and bases. What is water according to this definition? A)An acid and a base B)An acid C)A base D)Neither an acid nor a base

A)An acid and a base

Which compound would you say is not considered an organic compound? A)Calcium Carbonate B)Neither of them C)Vitamin C D)Benzene

A)Calcium Carbonate

There is some remaining sodium hydroxide-methanol solution that we have to dispose of. This solution poses several hazards, which of the following does NOT apply for the sodium hydroxide methanol solution? A)Explosive B)Corrosive C)Flammable D)Toxic

A)Explosive

What do you think is the reason for an increasing atomic radius within one group? A)Increasing number of electron shells B)Decreasing metallic character C)Decreasing number of neutrons D)Increasing electronegativity

A)Increasing number of electron shells

What do you think is the reason for a decreasing atomic radius within period one? A)Increasing number of protons B)Decreasing metallic character C)Decreasing number of neutrons D)Increasing electronegativity

A)Increasing number of protons

Periodic Table (Principles) To which of the three main chemical classes does Mercury (Hg) belong? A)Metals B)It's not an element in the periodic table C)Metalloids D)Nonmetals

A)Metals

Why is it important to work in the fume hood during this step? A)Methanol gets very volatile at high temperatures. B)The magnetic stirrer splashes base in all directions C)Sodium hydroxide is flammable D)Produced biodiesel is explosive

A)Methanol gets very volatile at high temperatures.

Which compound do you think it is? A)MgCl2 B)BeCl2 C)The mass does not match any of them, so it must be another compound. D)CaCl2

A)MgCl2

How would you write the conversion reaction from oil to biodiesel? A)Oil + alcohol + catalyst -> biodiesel + glycerol + catalyst B)Oil + alcohol + catalyst -> biodiesel C)Biofuel + alcohol + catalyst -> catalyst + biofuel + glycerol D)Oil + catalyst -> biodiesel + glycerol + alcohol

A)Oil + alcohol + catalyst -> biodiesel + glycerol + catalyst

What kind of phase change is happening to these particles? A)Sublimation B)Evaporation C)Freezing D)Condensation

A)Sublimation

Can you spot the difference between them? A)The bonds are different B)Compound B has more hydrogen C)Compound A has more carbons D)No, they are in fact all the same compound

A)The bonds are different

How does the number of moles of AgNO3 correlate to the number of moles of alkaline earth metal chloride? A)There should be twice as many moles of AgNO3 as XCl2 B)There should be half was many moles of AgNO3 as XCl2 C)There should be the same number of moles of each D)We cannot tell

A)There should be twice as many moles of AgNO3 as XCl2

What do these three images all have in common? A)They are all based on carbon compounds B)They are all fuels C)They are all foods D)They are all double-helical structures

A)They are all based on carbon compounds

What do the other elements in the same group as Krypton have in common? A)They have the same number of valence electrons B)They have the same number of electron shells C)They have the same number of protons D)They have the same atomic mass

A)They have the same number of valence electrons

What's the difference in concentration of hydronium ions between pH 1 and pH 4? A)Times 1000 B)Times 4 C)Time 10 D)Time 2.6

A)Times 1000

Looking at the results, can you determine which one is hexane? A)You cannot reach to a conclusion with these results B)It's compound F C)It's compound C D)It's compound B

A)You cannot reach to a conclusion with these results

Atoms and molecules are way too small to be seen, even with a microscope, so how can we count how many there are? A)You count them by mass B)You can't count atoms and molecules C)You count them by volume D)You count them using an electron microscope

A)You count them by mass

What is the definition of a base? A)Bases are proton donors B)Bases accept protons C)Bases donate protons to water molecules D)Bases increase the number of protons in an aqueous solution

B)Bases accept protons

Explosion! Which pat of the explosion event is NOT considered a chemical change? A)Water vapor is produced B)Carbon dioxide expands C)Ethanol reacts with oxygen D)Ethanol burns

B)Carbon dioxide expands

How should you dispose of the remaining methanol solution? A)Evaporate it in the fume hood B)Into the organic solvent waste C)Flush it down the sink D)Burn it inside the hood

B)Into the organic solvent waste

You may notice that the slope in the ice segment is steeper than the water segment. Why is that? A)More heat is required to raise the temperature of ice. B)More heat is required to raise the temperature of liquid water. C)More heat is required to melt ice than to evaporate it. D)Ice has a higher density than water thus it is easier to melt.

B)More heat is required to raise the temperature of liquid water.

Which of the following hazards does not apply for methanol? A)Flammable B)Oxidizing C)Health Hazard D)Toxic

B)Oxidizing

Which of the following answers is NOT a valid reason for the percentage yield of the reaction being below 100%? A)The unknown compound contained some impurities B)The product is not completely dry C)The precipitation was not complete D)Some product was stuck on the filter paper

B)The product is not completely dry

If you have a glass of pure water, without any acids or bases, how many hydronium ions (H3O+) do you expect? A)As many as there are water molecules B)The same number as OH- C)None D)Half the water is hydronium ions

B)The same number as OH-

In which of the pictures do you find the most particles? By particles, like sand grains, water molecules and iron atoms. A)In the water glass B)There are roughly the same amount of particles on each picture C)In the Sahara desert D)In the iron bol

B)There are roughly the same amount of particles on each picture

What is the smallest pH possible A)14 B)There is no fixed minimum C)1 D)0

B)There is no fixed minimum

From the heating curve, we can deduce the melting point and boiling point. What is the melting point of ethanol? A)78 degrees Celsius B)2.43 degrees Celsius C)-115 degrees Celsius D)105 degrees Celsius

C)-115 degrees Celsius

Guess how many water molecules self-ionize in one liter of water. A)10,000,000 moles B)1 mole C)0.000001 moles D)7 moles

C)0.000001 moles

What results from a reaction of a base (BOH) and a hydronium ion (H3O+)? A)H2O and BOH- B)Water and a strong acid C)2 H2O and B+ D)Water and a strong base

C)2 H2O and B+

Do you remember the symbol for oxidizing reagents? A)An exclamation mark B)A square with fragments C)A circle with flames D)A person with symptoms

C)A circle with flames

To figure out where the fallen out boxes go to in the periodic table wall we need to perform a couple of experiments. What kind of experiment would help you categorize some of the elements? A)Observe their shininess B)Test their ductility C)All are correct D)Measure their electrical conductivity

C)All are correct

Which compound is being shown on the holo-table? A)Butane B)Pent-1-ene C)But-1-ene D)Pentane

C)But-1-ene

In order for the gravimetric analysis to be valid, we want all of the chloride ions to precipitate. How can we ensure this? A)By adding the same volume of reactant B)By ensuring chloride ions are in excess C)By ensuring silver ions are in excess D)By having roughly the same amount of each reactant.

C)By ensuring silver ions are in excess

Which of these hazards could be removed by adding small amounts of certain solution? A)Flammability B)Toxicity C)Corrosiveness D)Neither of them

C)Corrosiveness

Which of the following solvents would be disposed in the halogenated solvent waste? A)Hexane B)Acetone C)DCM (Dichloromethane) D)Ethanol

C)DCM (Dichloromethane)

Which compound is not present? A)But-2-ne B)Ethyne C)Ethane D)Ethene

C)Ethane

Which element has the lowest electronegativity? A)Neon B)Helium C)Francium D)Lithium

C)Francium

What is the name of this compound? A)Methane B)Butane C)Hexane D)Ethane

C)Hexane

What is it about your predicted graph that makes it different from the heating curve you've recorded from the experiments? A)It shows all 3 states of matter clearly. B)It clearly shows the phase changes. C)It shows a continuous increase in temperature. D)It shows a rapid decrease in temperature.

C)It shows a continuous increase in temperature.

Ethanol, like any physical material in this universe, is matter. Which of these is not matter? A)Smoke B)Glass C)Light D)Bubbles

C)Light

Based on their phase of matter and what you already learned, which elements is clearly not a metal? A)Calcium B)Copper C)Neon D)Sodium

C)Neon

Does the intake of acidic or alkaline foods affect the blood pH? A)Yes, the pH increases after eating B)Yes, acidic food decreases pH and alkaline food increases it C)No, the blood pH is constant D)No, the blood pH fluctuates randomly

C)No, the blood pH is constant

Which group of elements have a full octet of electrons? A)Transition Metals B)Alkali Metals C)Noble Gases D)Halogens

C)Noble Gases

Which phase is the easiest to heat? A)Liquid metal B)Water C)Solid metal D)Ice

C)Solid metal

Can you spot the right statement for CH4 , H2CO, CO2? A)The valence of carbon is changing B)They are all organic molecules C)The angle of the carbon bond is different D)The carbon atoms are different sizes

C)The angle of the carbon bond is different

Why does the temperature remain constant during the phase changes? A)The substance does not require heat during the phase changes. B)No heat is added during the phase changes. C)The heat is used to convert the states of matter. D)The heat is not being absorbed by the substance.

C)The heat is used to convert the states of matter.

How are the pOH and pH linked? A)pH = 7 + pOH B)7 * pH = 14 - pOH C)pH + pOH = 14 D)7+pOH = pH-7

C)pH + pOH = 14

Applying the trends of oxidation states in the periodic table, what is a likely oxidation state of Chlorine? A)7 B)1 C)0 D)-1

D)-1

How many moles of AgNO3 should we use to be sure that we have excess, no matter which or the three compounds it is? A)0.025 mol B)0.050 mol C)0.075 mol D)0.100 mol

D)0.100 mol

When carbon binds to four other distinct atoms, what is the angle of the carbon bonds? A)120 degrees B)90 degrees C)180 degrees D)109.5 degrees

D)109.5 degrees

Imagine the two following scenarios: You pour a small amount of non-halogenated solvent into the halogenated waste. You pour a small amount of halogenated solvent into the non-halogenated waste. Which damage analysis is right? A)They are equally bad B)Small amounts do not matter - both are no problem C)1 is worse than 2 D)2 is worse than 1

D)2 is worse than 1

What is the carbon valence value? A)8 B)2 C)6 D)4

D)4

Methanol is volatile because it has a low boiling point. Have a look at the safety sheet. What is the boiling point of methanol? A)54 degrees Celsius B)76 degrees Celsius C)87 degrees Celsius D)65 degrees Celsius

D)65 degrees Celsius

Cl is part of the element family Halogens, which are also known as salt formers. How many valence electrons does Na have when forming an ionic bond with Cl? A)2 B)4 C)1 D)8

D)8

What precautions should you take when working with strong acids and bases? A)Only use plastic lab equipment B)Keep a Bunsen burner switched on and ready C)Only perform work in the fume hood D)Always wear goggles and gloves

D)Always wear goggles and gloves

Why is it important to use demineralized water? A)Because demineralized water has a higher boiling point than regular tap water. B)Because demineralized water poses less of a health hazard in chem labs. C)Because demineralized water has a lower density than regular tap water. D)Because demineralized water doesn't contain minerals.

D)Because demineralized water doesn't contain minerals.

What makes an acid? A)Temperature B)Number of protons in molecules C)Phase D)Chemical structure

D)Chemical structure

Where is the salicylic acid? A)Compound B B)Compound C C)Compound D D)Compound A

D)Compound A

Which compounds seem to have either an alcohol or phenol function? A)Compounds A and F B)Only compound A C)Compounds C, D, and E D)Compounds A, B, and D

D)Compounds A, B, and D

What kind of phase change is happening to these particles? A)Freezing B)Melting C)Evaporation D)Condensation

D)Condensation

Based on what you know about their location in the periodic table, what does Cs and Cl react to? A)CsCl3 B)CsCl4 C)CsCl2 D)CsCl

D)CsCl

When moving from left to right across a period, ionization energy is increasing? By which trend is this caused? A)Decrease in atomic mass B)Increase electrical conductivity C)Less electrons in the outer shell D)Decrease the atomic radius

D)Decrease the atomic radius

What kind of phase change is happening to these particles? A)Condensation B)Freezing C)Melting D)Depolarization (reverse of sublimation)

D)Depolarization (reverse of sublimation)

What are the different colors caused by that we can see in flame test? A)Metal atoms reacting with oxygen in the air B)Electrons being excited C)Metal ions reacting with chlorine D)Electrons falling back into their original shell

D)Electrons falling back into their original shell

What type of matter is ethanol 20% (v/v)? A)Heterogeneous mixture B)Element C)Compound D)Homogenous mixture

D)Homogenous mixture

What does the green color in the periodic table stand for? A)Non-metals B)Halogens C)Metalloids D)Noble Gases

D)Noble Gases

In the standard periodic table, the elements are listed in order of increasing atomic number. What does the atomic number represent? A)Number of electrons B)Number of neutrons C)Atomic Mass D)Number of protons

D)Number of protons

Which P-sentence indicates why you should work in the fume hood when using methanol? A)P363 and P330 B)P301 and P310 C)P210 and P233 D)P260 and P271

D)P260 and P271

Which of the elements you tested does not have a characteristic metallic appearance? A)Calcium B)Sodium C)Copper D)Phosphorus

D)Phosphorus

Can you see from the reaction stoichiometry how the number of the moles of AgCl formed correlates to the number of moles of AgNO3 consumed? A)There are twice as many moles of AgCl formed. B)It differs in the three different reactions C)There are half as many moles of AgCl formed D)The number of moles are the same

D)The number of moles are the same

"Why did you decide not to grab the fire extinguisher and fight the fire?" A)I needed to save my LabPad B)It's electrical and I already turned it off C)There was no extinguisher D)Too dangerous

D)Too dangerous

"I passed out because of the blast. What did you do after you pulled me out of the lab?" A)Extinguish the fire B)Close the fume hood C)Evacuate the building D)Trigger the alarm and break the circuit

D)Trigger the alarm and break the circuit

Which unit is used to express the acidity of an acid or alkaline solution? A)Karat B)Voltage C)Moles D)pH

D)pH


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