PLEASE HELP FOR CHEM TEST

Which is most closely associated with the Lewis dot diagrams for molecules that contain atoms of elements from the boron family,

Mkey [24]

The question is incomplete, the complete question is;

Which is most closely associated with the Lewis dot diagrams for molecules that contain atoms of elements from the boron family, Group 13 (Group IIIA)?

a. elements shown as 3+ ions

b. expanded octets of electrons

c. incomplete octets of electrons

d. odd number of valence electrons

e. kernel electrons promoted to the valance shell

Answer:

incomplete octets of electrons

Explanation:

A Lewis dot structure is a representation of a molecule based on the number of valence electrons on its valence shell. These electrons are shown as dots hence Lewis structures are also called dot electron structures.

For elements of group 13, they mostly form dimeric compounds due to the fact that their compounds possess an incomplete octet of electrons. This is common to group 13 elements, hence the answer above.

3 0

4 years ago

Which statements describe aspects of what causes wind to blow? Wind is caused by differences in air pressure. Wind moves from lo

soldier1979 [14.2K]

Answer:

The Correct Answer is A and C.

Explanation:

The wind is the movement of air, the movement of air is happened by the difference in pressure.

A difference in air pressure is what causes the wind to blow. Difference in pressure is happened by the uneven heating of the earth's surface.

The wind is normally moving air from a high air pressure place to a low air pressure place.

The greater the difference in air pressure the stronger the wind blow.

5 0

3 years ago

Read 2 more answers

You are a NASCAR pit crew member. Your employer is leading the race with 20 laps to go. He just finished a pit stop and has 5.0

jek_recluse [69]

Answer:

Since there are 3500 g of fuel left in the tank, and he needs only 1687.5 g to complete 20 laps, he has enough fuel to complete the race. I will tell the driver that he does not need to make another pit stop as he has enough fuel to complete the race.

Explanation:

Density = mass / volume

Density of fuel = 700 g/ 1 gal

Therefore, the mass of fuel in 1 gallon = 700 g

The driver has 5.0 gallons of fuel in the tank.

The mass of 5.0 gallons of fuel = 5 × 700 = 3500 g of fuel

Equation of the combustion of fuel, C₅H₁₂ is given below:

C₅H₁₂ + 8 O₂ ---> 6 H₂O + 5 CO₂

1 mole C₅H₁₂ requires 8 moles of O₂

1 mole of C₅H₁₂ has a mass = 72 g

8 moles of O₂ has a mass = 256 g

Therefore, 300 g of O₂ will require 300 × (72/256) g of C₅H₁₂ = 84.375 g of C₅H₁₂

84.375 g of fuel is used by the car per lap;

20 laps will require 20 × 84.375 g of fuel = 1687.5 g of fuel.

Since there are 3500 g of fuel left in the tank, and he needs only 1687.5 g to complete 20 laps, he has enough fuel to complete the race. I will tell the driver that he does not need to make another pit stop as he has enough fuel to complete the race.

7 0

3 years ago

Determine whether or not each mixture is a buffer. check all that apply. check all that apply. koh and nh3 hbr and nacl hcl and

erastova [34]

A buffer is usually composed of either:
- a weak base combined with its conjugate acid, or
- a weak acid combined with its conjugate base

Now, examining each of the choices:
1- KOH and NH3: since they are both bases, thus this mixture is not a buffer
2- HBr and NaCl: since HBr is a strong acid while NaCl is the salt of another different acid, thus this mixture is not a buffer
3- HCl and HBr: these are both considered to be strong acid, thus this mixture is not a buffer
4- HCHO2 and NaCHO2: as for HCH02, it is considered a weak base while NaCHO2 is considered its conjugate base, thus this mixture is a buffer

3 0

3 years ago

As a rock falls, some of its potential energy is transformed into kinetic energy. What is true about the mechanical energy durin

mars1129 [50]

Answer:

a or b

Explanation:

because those are the most likely to be true

now it gives you two options so i thinks it might be B but you could choose A you got two options choose wisely

4 0

2 years ago