Variables, experiments and exam technique Flashcards
What are the three main types of variables?
Dependent, independent and control.
What is the independent variable?
The thing you change, for example the concentration or temperature.
What is the dependant variable?
The thing you measure and look at at the end, for example the time it takes for the reaction to finish or volume of gas produced.
What is the control variable?
The thing you keep the same.
When do you do plus minus?(maths).
I think if the simplified numerator of the indicie is even but i need to check.
What is a pythagoreon triple?
Where all lengths are integers.
What are some examples of a pythagoreun triple?
3,4,5
8,15,17
5,12,13
7,24,25
What is a chord?
Any line that connects two parts of the circle(straight).
What is a sector?
Pizza part.
What is a segment?
Any part of it.
What does root6/root3 simple to?
root2.
Area of triangle?
Simplify/half at end.
What should you do when drawing a line of best fit?
MAKE IT CURVED.
What do all EM waves have in common?
They travel the same speed in a vacuum/space.
How are radio waves produced?
Produced by electrons in electrical circuits or Ariel’s.
How are gamma rays produced?
Random due to decay of nucleus in atom or fusion or fission. Also caused by annihilation in PET scanners.
Hydrogen.
Hydrogen burns with a squeaky pop noise.
What shouldnt you do?
Say it.
Explain.
Say why.
Positive or phytoextraction.
Decontaminates ground and uses low grade ores so preserves high grade ones for future.
What is good about electrolyis?
Produces pure metals.
Water.
Not crucial how much we have.
Remember.
Decreased rate because magnesium is more reactive.
Say.
So bla bla bla.
What colour is zinc.
Silver/grey.
What colour is copper sulfate?
Blue but zinc sulphate is colourless.
DO NOT SAY CLEAR.
SAY COLOURLESS.
What can measure pH?
A pH meter.
What can be used to measure liquids?
Pipette or measuring cylinder. Burette is the best.
Explain in terms of the particles present why the pH increases during the experiment.
Increase in pH is less acidic as hydrogen ions react with base to form eater because there a fewer hydrogen ions, the concentration of hydrogen ions has decreased and therefore the pH has increased because pH is the negative log of the concentration of hydrogen ions.
What colour are metals?
Silver.
Is black or white coloured in chem?
Black is.
What colour is copper oxide?
Black.
What colour is copper carbonate?
Green.
What colour solutions does copper make?
Blue.
Metal.
Large regular lattice.
For reversable.
A to half a plus water, add water to product to see if it makes A.
How many atoms would there be in one mole of CuI2?
3 times Avogadro as 3 atoms.
What other things have changed about our solar system?
Planets have moons, the earth rotates, Pluto is no longer a planet, orbits are elliptical not circular, our solar system is not the only one and the earth is a sphere not flat.
What is the evidence for expansion?
Red shift, light from distant galaxies shifted to red side of spectrum, doppler effect expanding at increasing rate due to dark energy. Observed wavelength of light is longer showing source moving away. Most galaxies show this.
What is the evidence for the universe beginning at a single point?
CMBR, microwave radiation left over from beginning, extrapolating, microwaves because of cooling and detected from all over the sky.
Units of measure.
Units of measure.
