When multiplying, the product must have the same number of significant figures as the factor with the least number of significant figures. 0.0041 has two significant figures, 2.00 has three significant figures, and 501 has three significant figures. The answer will have 2 significant figures.
They are more likely to be covalent as covalent compounds usually tend to be radical on the color spectrum with deep purples and blacks and even earwax colored.
