The force due to friction is generally independent of the contact area between the two surfaces. This implies regardless of whether you have two overwhelming objects of a similar mass, where one is half as long and twice as high as the other one, despite everything they experience the equivalent frictional power when you drag them over the ground.
Not 100% sure, but I'd have to say this:
When rounding for sig figs, you look at the other numbers in your calculation and see which one has the least amount of sig figs. This number is 2.70. (3 sig figs). So, you round to 3 significant figures in your calculation.
Hope this helped!
Molarity = Moles/Liter
Use the molecular atomic mass of NaCl to convert from grams to moles.
Molecular mass of NaCl is the sum of its atomic masses. Look at the periodic table to find these. Na is 23 g/mol and Cl is 35.5 g/mol ,
so NaCl = 23 + 35.5 = 58.5 g/mol
multiply to cancel out grams
76 g NaCl * (1mol / 58.5 g NaCl) = 1.3 mol NaCl
over 1 Liter is just 1.3 M NaCl
Carbon-12 has the following electron configuration: 1s2-2s2-2p2. As seen in the configuration, the right answer is: the first electron shell has 4 orbitals.
Because they have the same number of valence electrons.
