1 / 8

Equations – Computer Says No!

Equations – Computer Says No!. http://www.roystoncartoons.com/2009/11/cartoon-illustration-computer-says-no.html. Today’s Lesson. Go through answers to test Review of electron dot diagrams Drawing electron dot diagrams Working out masses from equations. Electron Dot Diagrams.

adelie
Download Presentation

Equations – Computer Says No!

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Equations – Computer Says No! http://www.roystoncartoons.com/2009/11/cartoon-illustration-computer-says-no.html

  2. Today’s Lesson • Go through answers to test • Review of electron dot diagrams • Drawing electron dot diagrams • Working out masses from equations

  3. Electron Dot Diagrams • In an electron dot diagram, you need to include the following: • Number of Neutrons and Electrons in the nucleus • The correct number of electrons in each shell • Up to 2 electrons in first shell • Up to 8 electrons in second shell • Up to 18 electrons in third shell • Etc – but your last shell normally has 8 electrons unless it has only 1 electron shell

  4. Sharing Electrons • For molecules, they like to share (covalent) or donate (ionic) electrons. • This is what we will be focusing on. I’ll draw some examples on the board. • Now we can complete a fun worksheet • I will also be collecting your workbooks around every 2-3 weeks from now on. As such, you need to write your answers in your books.

  5. The Mole • In Chemistry, we measure the mass of objects through ‘the mole’. • The mole is the mass of how many atoms or molecules there are. • It’s known as Avogadro’s Constant. There are 6.02 X 10^23 atoms of molecules in a mole. • Eg, there are 602000000000000000000000 atoms of Hydrogen in 1g.

  6. Masses From Equations • In an equation, both sides need to have the same mass or same amount of stuff • Eg; C (s) + O2 (g) -> CO2 (g) • 1 C Atom + 1 Oxygen Molecule = 1 molecule of Carbon Dioxide • 12 + 32 = 44g • See the pattern – both sides have the same mass 

  7. Calculating Mass From Equations • You need to do the following steps: • Write the balanced equation for the reaction • Write down the relative atomic mass (Ar) or formula mass for each substance • From the equation, write down the reacting amount in grams • Once you know these, you can find out the actual mass. • Next slide has an example

  8. H2OOOOH! • 2H2 (g) + O2 (g) -> 2H2O (l) • 2X2g + 32g 2 X 18g • 4g + 32g 36 g • We only have 1 g of H, so much Oxygen and water will we make?? • 4/4g + 32/4g 36/4g • 1 g 8g 9g • Complete Q 1, 2 & 3 on P 118/119

More Related