Random Chem questions?

How many significant figures are there in each of the following numbers?


05050.5


7.00 × 10^-5


1.23457


0.0012


0.0150 × 10^4





I get 15 tries to answer this. I have tried 14 times. I am getting 5,1,6,2,2 . What am I doing wrong?





Also:


Round 908535 to four significant figures


Round 89869 to two significant figures


Round 0.000010996 to four significant figures





Last but not least:


A pycnometer with a mass of 54.26 g when empty, has a mass of 103.09 g when filled with water (density = 1.000 g/mL), and a mass of 93.82 g when filled with liquid C.


What is the volume of the pycnometer?


What is the density of liquid C?

Random Chem questions?
5,3,6,2, 3 for the sig figs


in 7.00 the 0's are significant (why else would you put them there?)





908500


9.0 x 10^4


0.00001100





Volume of the pycnometer is 103.09-54.26 = 48.83 mL


So the density of 93.82/48.83 = 1.921 g/mL