Untitled Quiz

Podcast Beta

Play an AI-generated podcast conversation about this lesson

Questions and Answers

In an experiment, the variable that is not changed is referred to as the:

Dependent variable

Measurement variable

Independent variable

Controlled variable (correct)

When solutions of lithium fluoride (LiF) and lead chloride (PbCl2) are mixed, solid lead fluoride (PbF2) forms. Which ions remain dissolved in the solution?

Pb2+ and F-

Li+ and Cl-

Pb2+ and Cl-

Li+ and F- (correct)

The rate of a chemical reaction will increase if:

A catalyst is used (correct)

The temperature decreases

The surface area of the reactants decreases

The concentration of the reactants decreases

Which of the following is not a balanced equation?

NaCl + AgNO3 → AgCl + NaNO3 Signup and view all the answers

Which of the following is a covalent compound?

H2O Signup and view all the answers

Which of the following ions does not have a charge of ‘-2’?

Chromate Signup and view all the answers

In the periodic table, elements are placed in the same group because they have the same:

Number of valence (outermost) electrons Signup and view all the answers

The mass number of an element always indicates the number of:

Protons + neutrons Signup and view all the answers

In terms of collision theory, a chemical reaction only occurs when:

Reactants collide in correct orientation with sufficient energy Signup and view all the answers

In an energy level (profile) diagram, activation energy is a measure of:

the energy required for successful collisions to occur Signup and view all the answers

The use of fertilisers in farming which leads to waste entering the waterways such as rivers would be classified as what type of pollutant?

Chemical pollutant Signup and view all the answers

When an acid was added to a solid, a reaction occurred that produced a clear solution and a colorless gas. The gas popped when a lighted match was placed in the mouth of the test-tube. The gas must have been:

Hydrogen Signup and view all the answers

Name a possible formula for an ionic compound formed by the elements V, W, X, Y, and Z with their respective charges. Include subscripts as necessary.

W3Z2 Signup and view all the answers

Which of the following observations would be a quantitative observation?

The reaction finished after thirty-six seconds Signup and view all the answers

Which of the following is the correct naming for the following groups?

Noble gases - Halogens Signup and view all the answers

Write the letter corresponding to the element in the Periodic Table for each given criteria.

i) B, ii) D, iii) C, iv) E, v) F, vi) A Signup and view all the answers

Complete the table by providing the formula of the ionic compound formed by Fe3+ and SCN- ions.

Fe(SCN)3 Signup and view all the answers

Study Notes

Semester 1 Exam 2023: Year 10 Science - Chemistry

Multiple Choice Section

In an experiment, the controlled variable is the one that remains unchanged.
When solutions of lithium fluoride (LiF) and lead chloride (PbCl2) are mixed, solid lead fluoride (PbF2) forms, and Li+ and Cl- ions remain dissolved in the solution.
The rate of a chemical reaction will increase if a catalyst is used.
A covalent compound is H2O.
Chromate ions have a charge of -2.
In the periodic table, elements are placed in the same group because they have the same number of valence (outermost) electrons.
The mass number of an element indicates the number of protons + neutrons.
A chemical reaction only occurs when reactants collide in the correct orientation with sufficient energy.
Activation energy is a measure of the energy required for successful collisions to occur.
Fertilisers in farming can be classified as chemical pollutants.
When an acid is added to a solid, a reaction occurs, producing a clear solution and a colourless gas, which is likely to be carbon dioxide.

Short Answer Section

Question 1: Periodic Table

An alkali earth metal in period 4 is an element with symbol B.
An element with an electron configuration of 2.8.3 is H.
An element in period 3 with 5 electrons in the outermost shell is K.
An element with a full outer shell of electrons is L.
An element that would form an ion with a charge of -1 is M.
A metal with one valence electron is C.

Question 2: Ionic Compounds

The formula of an ionic compound FeI3 has ions Fe³⁺ and I⁻.

Question 3: Investigation of Aluminium Reaction

The balanced formula equation for the reaction is Al (s) + H2SO4 (aq) → Al2(SO4)3 (aq) + H2 (g).
Independent variable: concentration of acid.
Dependent variable: time taken for Aluminium to react completely.
Hypothesis: As the concentration of acid increases, the time taken for Aluminium to react completely decreases.
Safety precaution: Wear protective gloves and goggles.
Observations that confirm a chemical reaction has taken place: the beaker feels warm, and a colourless gas is produced.
According to collision theory, as the concentration of acid increases, the frequency of successful collisions increases, resulting in a shorter time for Aluminium to react completely.

Question 4: Calcium

Element Calcium-40: atomic number 20, atomic mass 40, electron configuration 2.8.8.2.

Question 5: Zinc and Hydrogen Gas

Zinc metal: metallic bonding, does not conduct electricity, malleable, has a high melting point.
Hydrogen gas: molecular bonding, does not conduct electricity, not malleable, has a low boiling point.

Question 6: Ionic Bonding

In a solid, ionic bonding is present, and the substance does not conduct electricity.
In a dissolved state, the ions are free to move, and the substance conducts electricity.

Question 7: Reaction of Potassium Carbonate and Barium Nitrate

The type of reaction is a precipitation reaction.
Word equation: Potassium carbonate + Barium nitrate → Potassium nitrate + Barium carbonate.
Balanced chemical equation: K2CO3 (aq) + Ba(NO3)2 (aq) → 2KNO3 (aq) + BaCO3 (s).

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.