How many significant figures are there in 0.004010? ( )
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The solubility of NaCl is 35.7 g/100 mL of water at 0 oC, and 39.12 g/100 mL of water at 100oC. A sample of 75 g NaCl was stirred overnight at 100oC with 200 mL water. Which statement is correct? ( )
A. The solution is unsaturated
B. The solution is saturated
C. The solution is supersaturate
D. It is hard to know from the conditions given
For a ClF4+ ion, how many valence electrons should be shown in the Lewis structure? ( )
A. 32
B. 33
C. 34
D. 35
The oxidation number of S in NaHSO3 is ( )
A. -2
B. 0
C. +4
D. +6
What is the highest oxidation number expected for sulfur in its compounds? ( )
A. +2
B. +4
C. +6
D. +8