It would be 23.46, since the next number is a 5 so we can round up.
Significant figures are:
ANY number that is not 0
Any 0 between two nonzero digits
Any 0 following a decimal (i.e 1.50)
An example of a heterogeneous catalyst is a catalytic converter. A catalytic converter is an emissions control device that converts toxic pollutants in exhaust gas to less toxic pollutants by catalyzing a redox reaction (oxydation or reduction).
Answer:
advantages:
. The error due to weighing the solute can be minimised by using concentrated stock solution that requires large quantities of solute. 2. We can prepare working standards of different concentrations by diluting the stock solution which is more efficient since consistency is maintained
3. Some of the concentrated solutions are more stable and are less likely to support microbial growth than working standards used in the experiments.
From the periodic table you get the atomic masses of each element.
These are the values that I have in my periodic table (use those numbers of your periodic table if your teache gave you a specific one)
Na: 23 g/mol
O: 16 g/mol
H: 1 g/mol
C: 12 g/mol
Ca: 40 g/mol
S: 32 g/mol
Mg: 24 g/mol
P: 31 g/mol
Now I will do some examples and you do the others:
1) NaOH: 1 atom of Na * 23 g/mol + 1 atom of O * 16 g/mol + 1 atom of H * 1 g/mol
=> 1*23g/mol + 1*16g/mol + 1*1g/mol = 40 g/mol
2) H2O
=> 2 atoms of H * 1 g/mol + 1 atom of O * 16 g/mol = 2*1g/mol + 1*16g/mol = 18 g/mol
3) Glucose: C6H12O6
6*12 g/mol + 12 * 1g/mol + 6*16 g/mol = 72g/mol + 12g/mol + 96 g/mol = 180 g/mol
4) CaSO4:
1*40 g/mol + 1*32g/mol + 4*16g/mol = 136 g/mol
Now you only have to do the last one by your own.
The answer is c :) i hope its the right answer