Introduction to Chemistry

idk bro for the test on 09-12-25

On an universal indicator, what colours and numbers would indicate acid?

Red to yellow and 1-6

On an universal indicator, what colours and numbers would indicate alkali?

Blue to purple and 8-14

On an universal indicator, what colour and numbers would indicate neutral?

7 and green.

what is the equation including mass, moles and Mr (relative formula mass)?

mass = moles x Mr

what is the equation including volume, moles, and 24dm³

volume = moles x 24dm³

What is the equation including mass, volume, and density?

mass = density x volume

What reagent is in excess?

The one with the higher number of moles

Which reagent is limiting?

The one with a lower number of moles. (use this value when calculating moles on the other side of equation)

Why might reactants be heated?

To speed up rate of reaction

How do you know when a reactant is used up?

When there is excess of another reactant

How do you work out percentage yield?

Percentage yield = actual yield/theoretical yield x 100

What is the equation including volume, moles, and concentration?

moles = volume x concentration

What is the equation for atom economy?

Atom economy = molar mass of desired product/sum of molar masses of all products x 100%

How to work our empirical formula?

Find the moles of each compound, then divide each compounds moles by the smallest mole number.

What is an independent variable?

What you change in an experiment

What is a dependent variable?

What you are measuring/trying to find out in an experiment

What is a control variable?

What you keep the same in repeats of an experiment