What is the name of the starting chemicals in a reaction?
Conservation of mass | Exit Quiz | Oak National Academy

Quiz
•
Science
•
9th Grade
•
Hard
Oak National Academy
FREE Resource
6 questions
Show all answers
1.
MULTIPLE CHOICE QUESTION
30 sec • 1 pt
ingredients
products
reactants
Answer explanation
Reactants are the starting chemicals in a reaction.
2.
REORDER QUESTION
1 min • 1 pt
Order the steps in a chemical reaction.
Formation of products
Rearrangement of atoms
Presence of reactants
Answer explanation
Start with the reactants, the atoms rearrange during the reaction to form the products.
3.
MULTIPLE CHOICE QUESTION
30 sec • 1 pt
Which of the following statements explains why mass is conserved in a chemical reaction?
atoms are destroyed
atoms change into different elements
atoms are not lost or gained, but rearranged
Answer explanation
Atoms are not lost or gained but rearranged in a chemical reaction, so the mass of the reactants will equal the mass of the products.
4.
MATCH QUESTION
1 min • 1 pt
10 g of magnesium is heated in a crucible and 12g of magnesium oxide is obtained at the end of the reaction. Match the questions to the answers below about this reaction.
What other reactant was present?
open
What could have happened to the product?
Some could have escaped into the atmosphere.
How much of this reactant reacted?
oxygen
What type of system was this?
12 g - 10 g = 2 g
Answer explanation
Oxygen was the other reactant, reacting with magnesium to form magnesium oxide. 2 grams of oxygen reacted, inferred from the mass increase of the magnesium oxide product. This was an open system. Some of the magnesium oxide could have escaped.
5.
MULTIPLE SELECT QUESTION
30 sec • 1 pt
Some open system reactions where a gas is used as a reactant or formed as a product, may appear as if there has been a gain or loss in mass. Choose the reactions below where this could be the case.
Na(s) + Cl₂(g) → NaCl(s)
Fe(s) + S(s) → FeS(s)
4Fe(s) + 3O₂(g) → 2Fe₂O₃(s)
2Al(s) + 3Br₂(l) → 2AlBr₃(s)
Ca(s) + 2HCl(aq) → CaCl₂(aq) + H₂(g)
Answer explanation
Na(s) + Cl₂(g) → NaCl(s) and 4Fe(s) + 3O₂(g) → 2Fe₂O₃(s) Chlorine and oxygen are used as reactants, so mass may appear to increase. Ca(s) + 2HCl(aq) → CaCl₂(aq) + H₂(g) hydrogen is a product and would escape so mass would appear to decrease.
6.
MULTIPLE CHOICE QUESTION
30 sec • 1 pt
Balance the following equation showing the combustion of a hydrocarbon by replacing X, Y and Z and add state symbols to show the expected state of the reactants and products. C₃H₈ + XO₂ → YCO₂ + ZH₂O
X = 5 (g), Y = 3 (g) and Z = 4 (l)
X = 4 (g), Y = 2 (g) and Z = 2 (g)
X = 3 (g), Y = 3 (g) and Z = 3 (g)
X = 5 (g), Y = 3 (g) and Z = 4 (g)
X = 2 (g), Y = 2 (g) and Z = 4 (g)
Answer explanation
The equation is C₃H₈(g) + 5O₂(g) → 3CO₂(g) + 4H₂O(g). The hydrocarbon is propane which is a gas. Water would also be in the gas state as combustion involves the release of much heat energy.
Similar Resources on Quizizz
10 questions
Atomic Structure

Quiz
•
8th - 12th Grade
10 questions
Reversible ⇌ Reaction

Quiz
•
10th - 11th Grade
10 questions
UNIT QUIZ

Quiz
•
10th Grade
10 questions
Macromolecules

Quiz
•
9th - 12th Grade
11 questions
8.6 E Check #1

Quiz
•
8th Grade - University
10 questions
JC1 Challenge 3

Quiz
•
11th Grade
10 questions
Stoichiometry Quiz (Bagsakan na this!!)

Quiz
•
12th Grade
8 questions
Fusion in stars

Quiz
•
9th - 12th Grade
Popular Resources on Quizizz
15 questions
Multiplication Facts

Quiz
•
4th Grade
20 questions
Math Review - Grade 6

Quiz
•
6th Grade
20 questions
math review

Quiz
•
4th Grade
5 questions
capitalization in sentences

Quiz
•
5th - 8th Grade
10 questions
Juneteenth History and Significance

Interactive video
•
5th - 8th Grade
15 questions
Adding and Subtracting Fractions

Quiz
•
5th Grade
10 questions
R2H Day One Internship Expectation Review Guidelines

Quiz
•
Professional Development
12 questions
Dividing Fractions

Quiz
•
6th Grade
Discover more resources for Science
25 questions
Spanish preterite verbs (irregular/changed)

Quiz
•
9th - 10th Grade
10 questions
Identify Slope and y-intercept (from equation)

Quiz
•
8th - 9th Grade
10 questions
Juneteenth: History and Significance

Interactive video
•
7th - 12th Grade
8 questions
"Keeping the City of Venice Afloat" - STAAR Bootcamp, Day 1

Quiz
•
9th - 12th Grade
26 questions
June 19th

Quiz
•
4th - 9th Grade
27 questions
STAAR English 1 Review

Quiz
•
9th Grade
20 questions
Understanding Linear Equations and Slopes

Quiz
•
9th - 12th Grade