18)
a. Ra
d. Ag
19)
a. C
b. Br
c. Mg
20)
a. S
b. Br
c. O
Sorry wasn’t sure about some of them in #18
Hope the notes are helpful.
True. Nuclear fusion of hydrogen to form helium occurs naturallyin the sun and other stars. It takes place only at extremely high temperatures.
Commensalism is the relation ship between two species where one of the species is being benefited while the other is not benefited and not even harmed.
It is a type of symbiosis
the correct answer is
A) Birds feed off the insects that are stirred up from the grasses as cattle move through.
Answer:
12:7
Explanation:
To Determine: To calculate the formula of the unknown binary compound of oxygen and nitrogen and to ratio in the next compound of the series using given data.Answer:The formula of the unknown compound .The ratio for atoms of oxygen to nitrogen inis .The mass ratio of oxygen to nitrogen in next member of the series of compounds is .Explanation:The mass ratio of toinis .The mass ratio of toin theunknown compound is .The atomic mass of the oxygen is .The atomic mass of the nitrogen is .The mass ratio of to in a molecule can be represented as: …… (1)Here,is the number of atoms of the oxygen in the molecule.is the mass of an atom of oxygen.is the number of atoms of the nitrogen in the molecule.is the mass of an atom of nitrogen.For unknown compound, substitutefor , for and for mass ratio in equation (1).The ratio of atoms of oxygen to nitrogen is , therefore, the expected formulas of the unknown compound is and . If the unknown compound is in a series with then the formula of the unknown compound and the formula for the next member of the series is .The ratio for atoms of oxygen to nitrogen inis .For , substitute 5 for , for , 2 for and for in equation (1).The mass ratio of oxygen to nitrogen in next member of the series of the compounds is .
Answer: penetration is the ability of an electron in a given orbital to approach the nucleus closely. Shielding refers to the fact that core electrons reduce the degree of nuclear attraction felt by the orbital electrons. Shielding is the opposite of penetration. The most penetrating orbital is the least screening orbital. The order of increasing shielding effect/decreasing penetration is s<p<d<f.
Explanation:
The order of penetrating power is 1s>2s>2p>3s>3p>4s>3d>4p>5s>4d>5p>6s>4f....
Since the 3p orbital is more penetrating than the 3d orbital, it will lie nearer to the nucleus and thus possess lower energy.
