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.

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.

So, there are 2 moles present in
particles of oxygen.
A warming climate can cause seawater to expand and ice over land to melt, both of which can cause a rise in sea level. Storm surge on a Louisiana highway shows the effects of rising sea levels. Many people are interested in climate change and how a changing climate will affect the ocean.
Answer:
The heat absorbed by the sample of water is 3,294.9 J
Explanation:
Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.
The sensible heat of a body is the amount of heat received or transferred by a body when it undergoes a temperature variation (Δt) without there being a change of physical state (solid, liquid or gaseous). Its mathematical expression is:
Q = c * m * ΔT
Where Q is the heat exchanged by a body of mass m, made up of a specific heat substance c and where ΔT is the temperature variation.
In this case:
- Q=?
- m= 45 g
- c= 4.184

- ΔT= Tfinal - Tinitial= 38.5 C - 21 C= 17.5 C
Replacing:
Q= 4.184
* 45 g* 17.5 C
Solving:
Q=3,294.9 J
<u><em>The heat absorbed by the sample of water is 3,294.9 J</em></u>
<u><em></em></u>
Answer:
Cell membrane
B
Explanation:
Capsules, fimbriae, pili, flagella, and even the cell wall
Q = mcΔθ
67.5 = m x 0.45 x (28.5 - 21.5)
M = 67.5 / 3.15
= 21.4 g