A. Would be the correct answer :-)
Answer:
By adding a surface that increases friction? Such as outdoor mats(rough ones), which increases friction between the bottom of the boots and the surface.
Answer:
the first one which is A
Explanation:
the burning of fossil fuels causes both air pollution and water pollution
Answer: (a) There are 0.428 moles present in 12 g of
molecule.
(b) There are 2 moles present in
particles of oxygen.
Explanation:
(a). The mass of nitrogen molecule is given as 12 g.
As the molar mass of
is 28 g/mol so its number of moles are calculated as follows.
![No. of moles = \frac{mass}{molar mass}\\= \frac{12 g}{28 g/mol}\\= 0.428 mol](https://tex.z-dn.net/?f=No.%20of%20moles%20%3D%20%5Cfrac%7Bmass%7D%7Bmolar%20mass%7D%5C%5C%3D%20%5Cfrac%7B12%20g%7D%7B28%20g%2Fmol%7D%5C%5C%3D%200.428%20mol)
So, there are 0.428 moles present in 12 g of
molecule.
(b). According to the mole concept, 1 mole of every substance contains
atoms.
Therefore, moles present in
particles are calculated as follows.
![Moles = \frac{12.044 \times 10^{23}}{6.022 \times 10^{23}}\\= 2 mol](https://tex.z-dn.net/?f=Moles%20%3D%20%5Cfrac%7B12.044%20%5Ctimes%2010%5E%7B23%7D%7D%7B6.022%20%5Ctimes%2010%5E%7B23%7D%7D%5C%5C%3D%202%20mol)
So, there are 2 moles present in
particles of oxygen.