Presentation is loading. Please wait.

Presentation is loading. Please wait.

Mass, particles, balanced

Published byAgus Tan Modified over 5 years ago

Similar presentations

Presentation on theme: "Mass, particles, balanced"— Presentation transcript:

1 Mass, particles, balanced
Learning Objective To be able to: Write balanced equations and use them to explain the conservation of mass Key Words: Mass, particles, balanced

2 Balancing Equations and Conservation of Mass
Saturday, 25 May 2019 Balancing Equations and Conservation of Mass Date and title in books. You need a pen, pencil & ruler. Starter Activity – 5 minutes Exam question

3 Explain the conservation of mass
Target 9-1 Identify the conservation of mass (F/H) Target 4-9 Write balanced symbol equations (H) Target 5-9 Explain the conservation of mass Extension: Application of Knowledge Target 8/9 Explain the conservation of mass using a balanced symbol equation Learning Outcomes

4 Conservation of Mass New substances are made during chemical reactions
However, the same atoms are present before and after reaction. They have just joined up in different ways. Because of this the total mass of reactants is always equal to the total mass of products. This idea is known as the Law of Conservation of Mass. Reaction but no mass change

5 Conservation of Mass There are examples where the mass may seem to change during a reaction. Eg. In reactions where a gas is given off the mass of the chemicals in the flask will decrease because gas atoms will leave the flask. If we carry the same reaction in a strong sealed container the mass is unchanged. Gas given off. Mass of chemicals in flask decreases Mg HCl Same reaction in sealed container: No change in mass 11.71

6 Activity What is the conservation of mass law?
Two hydrogen atoms react with one oxygen atom. What happens to these atoms? What new substance is made? Two oxygen atoms reacts with one carbon atom

7 What have you learnt? Can you apply your knowledge about the conservation of mass law? Lets find out!

8 Chemical formulae – what is the ratio of atoms?
The name of a chemical can also be written as a formula. A formula uses chemical symbols and numbers to show the ratio of atoms of each element present in the chemical. Name of salt Formula Ratio of atoms in salt calcium chloride CaCl2 Ca Cl 1 2 sodium sulphate Na2SO4 Na S O 2 1 4 magnesium sulphate MgSO4 Mg S O 1 1 4 magnesium nitrate Mg(NO3)2 Mg N O 1 2 6 calcium sulphate CaSO4 Ca 1 S 1 O 4

9 What is the ratio of atoms in each salt?
Name of salt Formula Ratio of atoms in salt sodium chloride NaCl 1 Na 1 Cl magnesium chloride MgCl2 1 Mg 2 Cl potassium nitrate KNO3 1 K 1 N 3 O potassium sulphate K2SO4 2 K 1 S 4 O calcium nitrate Ca(NO3)2 1 Ca 2 N 6 O

10 Writing equations using chemical formulae
The names of chemicals in a word equation can be replaced with chemical formulae. When a chemical reaction is written using chemical formulae, the equation must be balanced. zinc hydrogen hydrochloric acid zinc chloride Zn HCl → ZnCl H2 2 1 Zn 1 H, 1 Cl 2 H, 2 Cl 1 Zn, 2 Cl 2 H Write down the formula for each chemical. Count the number of atoms on each side of the equation. Where needed, adjust the numbers in front of the formula so that the numbers of atoms on each side are balanced.

11 Writing and balancing chemical equations
Use chemical formulae to write a balanced chemical equation for the reaction between lead and hydrochloric acid. lead hydrochloric acid lead chloride hydrogen Pb HCl → PbCl H2 2 Use chemical formulae to write a balanced chemical equation for the reaction between calcium oxide and hydrochloric acid. calcium hydrochloric acid calcium chloride hydrogen Ca HCl → CaCl H2 2

12 Your Task Can you write and balance equations? Lets find out!

13 True or False Quiz! Atoms can be destroyed in a reaction
The atoms you start with in a reaction are the atoms you end with Atoms cannot be rearranged into different compounds All atoms are the same Some mass is lost during a reaction as it becomes a gas

Download ppt "Mass, particles, balanced"

Similar presentations

Balancing Chemical Equations

Balancing Chemical Equations
Reactions of metals with acid

Reactions of metals with acid
When a lump of zinc is added into copper sulfate solution, the two slowly react to produce very small dark copper granules and zinc sulfate solution.

When a lump of zinc is added into copper sulfate solution, the two slowly react to produce very small dark copper granules and zinc sulfate solution.
Calculating Reacting Masses

Calculating Reacting Masses
Chemical Formulae and Balancing Chemical Equations.

Chemical Formulae and Balancing Chemical Equations.
SECTION 3.2 Writing Chemical Equations. Objectives At the end of this lesson, you will be able to: Translate chemical word equations into formula equations.

SECTION 3.2 Writing Chemical Equations. Objectives At the end of this lesson, you will be able to: Translate chemical word equations into formula equations.
Counting Atoms and Balancing Chemical Equations. Identifying Compounds Each new element is identified by a capital letter Each new element is identified.

Counting Atoms and Balancing Chemical Equations. Identifying Compounds Each new element is identified by a capital letter Each new element is identified.
Law of Conservation of Mass Law of Conservation of Mass: Mass is neither created nor destroyed during a chemical reaction- it is conserved Mass reactants.

Law of Conservation of Mass Law of Conservation of Mass: Mass is neither created nor destroyed during a chemical reaction- it is conserved Mass reactants.
Chemical Reactions and Equations CLASS NOTES. Review from last class What types of changes can occur as a result of chemical reactions? – Can you give.

Chemical Reactions and Equations CLASS NOTES. Review from last class What types of changes can occur as a result of chemical reactions? – Can you give.
Section 10.1.  Balance skeleton equations  Balance word equations.

Section  Balance skeleton equations  Balance word equations.
Chemical Reactions. Chemical Reaction _______________ – process by which the atoms of one or more substance are rearranged to form different substances.

Chemical Reactions. Chemical Reaction _______________ – process by which the atoms of one or more substance are rearranged to form different substances.
Conservation Of Mass L.O: To understand that atoms are never created or destroyed therefore mass of reactants = mass of products Wednesday, October 14,

Conservation Of Mass L.O: To understand that atoms are never created or destroyed therefore mass of reactants = mass of products Wednesday, October 14,
(2.3) CHEMICAL EQUATIONS (p144-145). Recall: Word Equation A word equation - states what reacts and what is produced - uses words instead of formulas.

(2.3) CHEMICAL EQUATIONS (p ). Recall: Word Equation A word equation - states what reacts and what is produced - uses words instead of formulas.
Reactions. DON’T COPY pink WRITING. Acid + base This is a common reaction and needs to be remembered for exams. ACID + BASE -> SALT + WATER E.g. hydrochloric.

Reactions. DON’T COPY pink WRITING. Acid + base This is a common reaction and needs to be remembered for exams. ACID + BASE -> SALT + WATER E.g. hydrochloric.
Chemical Equations Learning Objective:

Chemical Equations Learning Objective:
WRITING CHEMICAL EQUATIONS THX.. The 4 steps; 1. Write the reaction down in words. This is often called the word equation 2. Replace each name with the.

WRITING CHEMICAL EQUATIONS THX.. The 4 steps; 1. Write the reaction down in words. This is often called the word equation 2. Replace each name with the.
Ionic equations A chemical equation shows the number of atoms and molecules of the reactants and products. Also shows physical state of reactants and products.

Ionic equations A chemical equation shows the number of atoms and molecules of the reactants and products. Also shows physical state of reactants and products.
Balancing equations. Law of Conservation of Mass This law states that matter is never created or destroyed during a chemical reaction but is instead just.

Balancing equations. Law of Conservation of Mass This law states that matter is never created or destroyed during a chemical reaction but is instead just.
Unit: Chemical Reactions Balancing chemical equations.

Unit: Chemical Reactions Balancing chemical equations.
Counting Atoms and Balancing Chemical Equations. Elements, Compounds, Mixtures Hydrogen is an element. Hydrogen is an element. Oxygen is an element. Oxygen.

Counting Atoms and Balancing Chemical Equations. Elements, Compounds, Mixtures Hydrogen is an element. Hydrogen is an element. Oxygen is an element. Oxygen.

Similar presentations

Ads by Google