Download presentation

1
Avogadro and the Mole

2
**HIGHER GRADE CHEMISTRY CALCULATIONS**

Avogadro and the Mole.. Avogadro’s constant is the number of ‘elementary particles’ in one mole of a substance. It has the value of 6.02 x 1023 mol-1. Worked example 1. Calculate the number of atoms in 4 g of bromine. Step 1:- Identify the elementary particles present Br2 molecules 1 mole x 1023 Br2 molecules Step 2:- Change from moles to a mass in grams 160g x 1023 Br2 molecules Step 3:- Use proportion. 4 g /160 x 6.02 x 1023 Br2 molecules x 1023 Br2 molecules Step 4:- Change from number of molecules to number of atoms. 1.505 x 1023 Br2 molecules 2 x x 1023 Br atoms x 1023 Br atoms

3
**Calculations for you to try. **

How many atoms are there in 0.01 g of carbon? The elementary particles C atoms. 1 mole x C atoms. 12 g x C atoms. So g 0.01/12 x 6.02 x C atoms. x 1020 C atoms How many oxygen atoms are there in 2.2 g of carbon dioxide? The elementary particles CO2 molecules. 1 mole x CO2 molecules 44 g x CO2 molecules So g 2.2/44 x 6.02 x C atoms. x CO2 molecules The number of oxygen atoms 2 x 3.01 x 1022 x O atoms Higher Grade Chemistry

4
**Calculations for you to try. **

Calculate the number of sodium ions in 1.00g of sodium carbonate. The elementary particles (Na+)2CO32- formula units 1 mole x 1023 (Na+)2CO32- formula units 106g x 1023 (Na+)2CO32- formula units So g 1.00/106 x 6.02 x (Na+)2CO32- formula units x (Na+)2CO32- formula units The number of Na+ ions 2 x 5.68 x 1021 x 1022 Na+ ions 4. Calculate the number of protons in 0.1g of nitrogen gas? The elementary particles N2 molecules. 1 mole x N2 molecules 28 g x N2 molecules So g 0.1/28 x 6.02 x C atoms. x N2 molecules The number of N atoms 2 x 2.15 x 1022 The number of protons 7 x 2 x 2.15 x 1022 x 1023. Higher Grade Chemistry

5
**Calculations for you to try.**

5. A sample of the gas dinitrogen tetroxide, N2O4, contained x 1022oxygen atoms. What mass of dinitrogen tetroxide was present? The elementary particles N2O4 molecules 1 mole x N2O4 molecules 1 mole x x O atoms x O atoms So x O atoms mol of N2O4 2.408 x 1022 2.408 x 1024 mol 1 mole of N2O4 g So mole g Higher Grade Chemistry

Similar presentations

OK

Chemistry I The Mole SAVE PAPER AND INK!!! When you print out the notes on PowerPoint, print "Handouts" instead of "Slides" in the print setup. Also, turn.

Chemistry I The Mole SAVE PAPER AND INK!!! When you print out the notes on PowerPoint, print "Handouts" instead of "Slides" in the print setup. Also, turn.

© 2017 SlidePlayer.com Inc.

All rights reserved.

Ads by Google

Animated ppt on reflection of light Differential display ppt on tv Ppt on polynomials of 91 Ppt on international maritime organisation Ppt on railway reservation project Ppt on famous indian entrepreneurs list Ppt on tunnel diode amplifier Ppt on professional body language Ppt on computer hardware components Ppt on cells and batteries