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The student did another experiment using 20 cm3 of sodium hydroxide solution with a concentration of 0.18 mol/dm3 . Relative formula mass (Mr) of NaOH = 40 Calculate the mass of sodium hydroxide in 20 cm3 of this solution.

20/1000 *0.18 final answer 0.144 Answer must be explained in person. It is very difficult to explain in writing.
SG
Answered by Saranya G. • Chemistry tutor
5226 Views

Why is there a significant difference between the radii of first and second row transition metals, where as no difference (or even a decrease) is observed between the second and third rows?

The answer stems from the lanthanide (or lanthanoid) contraction. In more detail, there is a steady decrease in the radii of atoms from Lanthanum through to Lutetium, despite the associated increase in the a...
IB
Answered by Ioannis B. • Chemistry tutor
3266 Views

Why do ionisation energies have a general increase across periods?

Ionisation energy is the energy required for one mole of gaseous atoms to lose one mole of electrons, hence forming one mole of gaseous ions.The ionisation energies for elements increases across the period b...
AP
Answered by Anna P. • Chemistry tutor
3521 Views

Why is the nos form of 'jugar', spelt 'jugamos' and not 'juegamos'

The nos form of 'jugar' is spelt 'jugamos' and not 'juegamos' because it is a radical changing verb. This means that the stem of the verb does not stay the same as it would with regular verbs, such as comer ...
HB
Answered by Hannah B. • Spanish tutor
6883 Views

A compound is found to contain 3.1% Hydrogen, 65.3% Oxygen and 31.6% Phosphorus. Work out its empirical formula.

To answer this question, we need to know the relative number of atoms of each element present. This can be calculated by dividing the amount of an element present in the sample by the relative masses of that...
AB
Answered by Adam B. • Chemistry tutor
6451 Views