Answer:
The atoms are ranked in decreasing order as follows:
Fluorine ---4
Carbon ----3
Boron ------2
Beryllium --1
Explanation:
Effective nuclear charge (Zeff) is defined as the difference between the actual nuclear charge (the atomic number, Z) and the shielding constant (S).
It is calculated by finding the atomic number and electronic configuration, attributing a shielding value to each electron, adding all the shielding values and using the formula:
Z eff = Z - S
Effective nuclear charges:
An atom of carbon: 3.25
An atom of fluorine: 5.20
An atom of beryllium: 1.95
An atom of boron: 2.60
Answer:
C
Explanation:
You can’t round a phone number or Pin code
why would you round your birth year?
Solids are defined by the following characteristics:
definite shape (rigid)
definite volume.
particles vibrate around fixed axes.
Well, figures for efficiency vary a lot, but according to Bicycling Science it’s lubrication that matters most – lubing a dry chain can add 5% to the efficiency.
More interestingly (and I hadn’t read this bit in the book before) it varys a lot depending on gear ratio – bottom gear (22-28) is 99% efficient, top gear (42-11) is 88%. That’s a big difference