Chemidy Round 1

General Chemistry

100

Which solubility cat is the cutest?

Hydroxides :)

200

What conditions cause a solution with a phenolphthalein indicator to turn pink?

Alkaline/Base Conditions.

300

What are the 4 factors that determine the rate of reaction?

Temperature, Concentration, Surface Area, Catalyst

400

I have 2.05g/L of Nitrogen Dioxide. Convert this to micrograms per litre (µg/L) (also known as parts per billion ppb/L). 

2.05g/L x 10³ = 2050mg/L

2050mg/L x 10³ = 2,050,000 µg/L

500

What is the Net Ionic Equation of MgCl_{2 (aq)} + AgNO_{3 (aq)} --> AgCl_(s) + Mg(NO₃)_{2 (aq)}

Balance the equation also.

2Cl^-_(aq) + 2Ag⁺_(aq) --> 2AgCl_(s)

Organic Chemistry

100

Define a Polymer

A chain-link of smaller molecules known as monomers

200

What is an isomer? 

For bonus 200 Points draw an isomer of Hexane

Same molecular formulae, different structure/arrangement.

Anything with the formula C₆H₁₄

300

Name 3 different types of functional groups that contain a double-bonded oxygen

Aldehyde, Ketone, Carboxylic Acid, Amide, Ester

400

What are the four types of secondary bonds and order their attraction from strongest to weakest.

1. Ion-Dipole

2. Hydrogen-Bonding

3. Dipole-dipole

4. Dispersion 

500

I mix a pent-2-ene solution with bromine water. Draw me the chemical reaction and name the final compound. 

Should have the double bond replaced with the bromine (Image #1).

Name: 2,3-Dibromopentane

Thermochemistry

100

What are the products of a complete combustion reaction?

CO₂ + H₂O

200

Draw me an Exothermic Energy Profile Diagram (with activation energy & enthalpy)

Image #2

300

I decide I want to burn some Polyester for fun! Polyester is a thermoplastic. Will it melt? Explain using bond interactions.

Polyester will melt under heat because it does not contain the strong secondary covalent bonds in its structure. (Image #5)

400

Ethanol (C₂H₅OH) is a liquid at room temperature. The molar enthalpy of ethanol is -1435 KJ/Mol. Write me a complete thermochemical equation for the complete combustion of ethanol.

Include all states of matter and molar enthalpy.

C₂H₅OH_(l) + 7O_2(g) --> 3H₂O_(g) + 2CO_{2 (g)}

500

I burn 5g of ethanol to heat up 150ml of water by 5^oC. Find the molar enthalpy (ΔH).

Hint: Molar Mass of Ethanol is 46.068g/mol

Q=mcΔT

Q=150x4.18x5

Q=3,135J

ΔH=Q/n

n=m/M

n=5g/46.068g/mol

n=0.109mols

ΔH= 3,135J ÷ 1000/0.109mols

ΔH=-28.76kj/mol

Electrochemistry

100

What is reduction?

The gaining of an electron (e^-)

200

What are the Oxidation States of the specified elements in the following compounds:

1. Carbon in CO

2. Fluorine in FH

3. Manganese in Mn(SO₄)₂

1. +2

2. -1

3. +4

300

In this equation what is the reducing agent and the oxidising agent?

Fe₂O₃ + 3CO --> 2Fe + 3CO₂

Iron (III) Oxide is the oxidising agent (it gained electrons)

Carbon Dioxide is the reducing agent (it lost electrons)

400

Write the balanced half equation of dichromate (Cr₂O₇^-2) to chromium (III) ions (Cr⁺³) in acidic conditions.

6e^- + 14H⁺ + Cr₂O₇^-2  --> 2Cr⁺³ + 7H₂O

500

Draw a galvanic cell with lithium and copper metal (labelling the anode, cathode, solution of the metals as sulphates, salt bridge, flow of electrons.)

Image #4

Acid-Base Chemistry

100

What is a Strong Acid?

An acid that ionizes (H⁺) completely in a solution of water

200

Generally are non-metal oxides acidic or basic?

Non-metal oxides are generally acidic

300

What are the products of Sulphuric Acid (H₂SO₄) reacting with Sodium Hydroxide (NaOH) (Chemical equation required)

Sodium Sulphate + Water 

H₂SO₄ + 2NaOH --> Na₂SO₄ + 2H₂O 

400

Zinc oxide (ZnO) is an amphoteric oxide. Write two equations to represent this property.

ZnO + 2HCL --> ZnCl₂ + H₂O

ZnO + 2NaOH --> Na₂ZnO₂ +H₂O

500

The pH level of Lake Neutral was 8.2. Calculate the concentration of proton ions (H⁺) in the lake.  

[H⁺]=10^-8.2

[H⁺]=6.31 X 10^-9