Answer:
Matter
Compound
Explanation:
Caffeine is NOT an Element, because it is formed by different elements (C, H, N, and O).
Caffeine is NOT an Isotope, because this only applies to elements with the same atomic number but different mass number.
Caffeine is Matter because it has mass and occupies space by having volume.
Caffeine is a Compound because it has a formula with a <em>definite constant composition</em> of different elements.
In an ionic bond, electrons are transferred from one stone to another atom (shared).
Answer: 2.4 ml
Solution :
Molar mass of
= 17 g/mole
Given,: 28% w/w of
solution means 28 g of ammonia in 100 g of solution.
Mass of solution = 100 g
Now we have to calculate the volume of solution.
Molarity : It is defined as the number of moles of solute present in one liter of solution.

where,
n = moles of solute 
= volume of solution in liter = 0.11 L
Now put all the given values in the formula of molarity, we get

Using molarity equation:



Answer:
54g
Explanation:
Given parameters:
Number of moles of H₂O = 3 moles
Unknown:
mass of water = ?
Solution:
To solve this problem, we use the expression below:
mass = number of moles x molar mass
Molar mass of H₂O = 2(1) + 16 = 18g/mol
Mass of water = 3 x 18 = 54g