CHEM 1120 Experiment 4: Pigment Synthesis

Which reaction is occurring in the test tube?

Select one:
Mg(s) + HCl(aq) ⟶ MgCl2(aq) + H2(g)
HBr(aq) + LiOH(aq) ⟶ LiBr(aq) + H2O(l)
KCl(aq) + AgNO3(aq) ⟶ AgCl(s) + KNO3(aq)
C(s) + O2(g) ⟶ CO2(g)
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Terms in this set (12)
Which reaction is occurring in the test tube?

Select one:
Mg(s) + HCl(aq) ⟶ MgCl2(aq) + H2(g)
HBr(aq) + LiOH(aq) ⟶ LiBr(aq) + H2O(l)
KCl(aq) + AgNO3(aq) ⟶ AgCl(s) + KNO3(aq)
C(s) + O2(g) ⟶ CO2(g)
KCl(aq) + AgNO3(aq) ⟶ AgCl(s) + KNO3(aq)

The image shows a precipitation, in which a solid product is formed from two reactant solutions. Thus, the reaction equation matching the test tube in the image needs to have aqueous reactants on the left side of the reaction arrow and a solid product on the right side of the reaction arrow.
Image: Which reaction is occurring in the test tube? Select one: Mg(s) + HCl(aq) ⟶ MgCl2(aq) + H2(g) HBr(aq) + LiOH(aq) ⟶ LiBr(aq) + H2O(l) KCl(aq) + AgNO3(aq) ⟶ AgCl(s) + KNO3(aq) C(s) + O2(g) ⟶ CO2(g)
Determine whether each observation generally corresponds to a physical change or a chemical change.

A solution heats up upon mixing with another.
A solid dissolves into water.
Bubbles are produced upon mixing two solutions.
A precipitate is formed from two solutions.
A liquid freezes into a solid.
The color of a substance changes over time.
A solution heats up upon mixing with another. (Chemical Change)
A solid dissolves into water. (Physical Change)
Bubbles are produced upon mixing two solutions. (Chemical Change)
A precipitate is formed from two solutions. (Chemical Change)
A liquid freezes into a solid. (Physical Change)
The color of a substance changes over time. (Chemical Change)
What is the molar mass, in g/mol, of the hydrate compound with the proposed formula of Cr Cl3⋅3H2O
The molar mass of a hydrate compound is the molar mass of the ionic compound plus the molar mass of water multiplied by the number of waters of hydration in the formula. Determine the molar masses of CrCl3 and H2O by adding up the individual molar masses of the elements from the periodic table. Then, multiply the molar mass of water by the number of waters in the formula, which is 3 , and add the molar mass together.

molar mass of CrCl3⋅3H2O = molar mass of CrCl3 +( 3) (molar mass of H2O)

molar mass of CrCl3⋅3H2O = 158.36 g/mol + (3) (18.02 g/mol)

molar mass of CrCl3⋅3H2O = 212.42 g/mol
Consider each hydrate formula and use the options to complete its name.

Formula: CaCl2⋅2H2O
Name = ???
Formula: FeSO4⋅7H2O
Name = ???
Formula: MgCO3⋅3H2O
Name = ???
Formula: CaCl2⋅2H2O
Name = calcium chloride dihydrate
Formula: FeSO4⋅7H2O
Name = iron (ii) sulfate heptahydrate
Formula: MgCO3⋅3H2O
Name = magnesium carbonate trihydrate
Which procedure cannot be performed on a hot plate, requiring a Bunsen burner instead?

Select one:

Heating an isolated solid to dry it
Heating a solvent to help the solute dissolve
Heating a crucible to remove water from a hydrate
Heating water to boiling for a water bath
Heating a crucible to remove water from a hydrate
When preparing for work in the fume hood, be sure to gather all necessary tools, glassware, and chemicals (???) to minimize the number of times the hood sash is raised and lowered.
Work as much as possible in the (???) of the work surface to keep the area tidy and promote air flow.
If you need to step away from the experiment to obtain another item, (???) the sash during this time.
When preparing for work in the fume hood, be sure to gather all necessary tools, glassware, and chemicals in advance to minimize the number of times the hood sash is raised and lowered.
Work as much as possible in the middle of the work surface to keep the area tidy and promote air flow.
If you need to step away from the experiment to obtain another item, lower the sash during this time.
Which compounds could be represented by the empirical formula CH2?

Select one or more:

C3H6
C2H4
C2H2
C8H18
C8H16
C2H6
C3H6
C2H4
C8H16
Consider the balanced equation of aluminum reacting with sulfuric acid.

2Al + 3H2SO4 ⟶ Al2(SO4)3+ 3H2

Determine how many atoms of each element are present on each side of the arrow.

Al: ?
H: ?
S: ?
O: ?
Al: 2
H: 6
S: 3
O: 12
When balancing a redox reaction, begin by separating the reaction into (???). Balance each of these in terms of (???). Multiply by some factor if necessary so that the number of (???) appearing in both is the same. Add these together, canceling out any terms that appear on both sides of the final equation.
When balancing a redox reaction, begin by separating the reaction into half reactions. Balance each of these in terms of atoms and charge. Multiply by some factor if necessary so that the number of electrons appearing in both is the same. Add these together, canceling out any terms that appear on both sides of the final equation.
Once the vacuum filtration set-up is complete, start by adding a small amount of water in the filter funnel. Then, (???) the mixture (???)
Once the vacuum filtration set-up is complete, start by adding a small amount of water in the filter funnel. Then, slowly decant the mixture into the middle of the filter paper.
Suppose you are titrating an acid solution with a base solution of known concentration. To calculate the concentration of the acid solution, use three steps. 1. Use the (???) of base (???) the endpoint and the known concentration of the base solution to find the (???) of base used. 2. Use the (???) to find the moles of acid from the moles of base. 3. Divide the moles of acid by the volume of (???) the titration to find the concentration of acid..1. Use the delivered volume of base to reach the endpoint and the known concentration of the base solution to find the moles of base used. 2. Use the molar ratio to find the moles of acid from the moles of base. 3. Divide the moles of acid by the volume of acid solution before the titration to find the concentration of acid.After a mixture has been poured through filter paper, the (???) component remains on top while the (???) flows through. To collect the solid, spread the filter paper (???) and allow the solvent to (???)After a mixture has been poured through filter paper, the solid component remains on top while the liquid flows through. To collect the solid, spread the filter paper on a watch glass and allow the solvent to evaporate.