Answer:

Explanation:
Aly's teacher said some bacteria can be as small as 0.00365 cm long.
In this problem, we need to write the length of the bacteria written in scientific notation. Any number can be written in the form of scientific notation as follows :

a is a real no and b is an integer
In the given number, there are two zeroes before 3. We need to shift the decimal after 3. It can be done as follows :

Hence, this is the required solution.
Answer: 0.5 moles
Explanation:
Cr2(SO3)2 is the chemical formula for chromium sulphate.
Given that,
Amount of moles of Cr2(SO3)2 (n) = ?
Mass of Cr2(SO3)2 in grams = 128.9g
For molar mass of Cr2(SO3)2, use the atomic masses:
Chromium, Cr = 52g;
Sulphur, S = 32g;
Oxygen, O = 16g
Cr2(SO3)2 =
(52g x 2) + [(32g + 16g x 3) x 2]
= 104g + [(32g + 48g) x 2]
= 104g + [80g x 2]
= 104g + 160g
= 264g/mol
Since, n = mass in grams / molar mass
n = 128.9g / 264g/mol
n = 0.488 mole [Round the value of n to the nearest tenth which is 0.5
Thus, there are 0.5 moles in 128.9 grams of Cr2(SO3)2
Far apart and have weak attractive forces between them
<span>Molecules condense when the temperature decreases :)</span>