C1 Flashcards
What’s a compound
2 or more elements chemically combine
What’s an element
Made of the same atom (Mg,S,Cl)
What’s a mixture
Elements not chemically combine has high melting and boiling points
What is a molecule
Elements chemically combine and can be the same element
How do you work out the number of protons ?
Mass no. - atomic number
What is the protons relative charge and it’s relative mass
Relative charge: +1
Relative mass: 1
What’s the electrons relative charge and it’s relative mass
Relative charge: 0
Relative mass: 1
What’s the neutrons relative charge and it’s relative mass
Relative charge: -1
Relative mass: very small 0.0001
What was the ‘plum pudding model’ and what investigation was used to test this theory
He thought electrons were tiny negative charged particles and he tested this using the alpha-scattering experiment.
He used a fire alpha particle and fired atoms at gold foil
He found most we’ve straight through, some deflected and done bounced back. Showing atoms to be mainly empty with a positive middle and mass concentrated at the middle
What is the ‘nuclear model’
Electrons are located around the nucleus at specific distances known as shells around the shells in empty space
What is the ‘updated nuclear model’
It’s a positive nucleus made of protons and neutrons with shells around the nucleus with electrons which are negatively charged
What is filtration of an insoluble solid
You need a filtered funnel with filter paper, pour the mixture into the funnel and the water passes through, the solids are left in the filter paper
What is simple distillation separating liquid from solid
We heat the liquid which starts to evaporate the water then rises up the tube to the condenser and turns back to a liquid the water is left in the beaker and solids in the flask
What is chromatography and how do you do it? Separating different substances of solubility
Colour are put on chromatography paper in a solvent, the solvent makes its way up the paper
What is the stationary and mobile phase of chromatography
Stationary: paper
Mobile:solvent the dots that appear up the chromatography paper
We can use this to find an unknown substance to find how it moved from the measure line
Rf= distance moved my substance / distance moved my solvent
What is crystallisation of a solvable solid?
If we leave a solution out for a couple of days the water will evaporate leaving a solid NaCl.
To make crystallisation happen faster we can heat up the solution but not too much that it damaged the solid.
What is fractional distillation to separate a liquid from a liquid?
We take the solution and heat it with a lower boiling point than the other liquid, the liquid evaporates it goes to the fractional column and drips to the flask. Repeating this, increases the volume of the lower BP liquid. The two liquids increase temp and pass through the condenser and turn to a liquid. So as the temp increases the higher BP liquid goes through the process creating a pure liquid.
Name a separation technique that could be used to separate a solvable solid from a solution
Evaporation
What’s the technique used to separate a mixture of liquids with similar boiling points
Fractional distillation
What determines a metals rate of reactivity
How fast it can form a positive ion
