Benzoic acid reacts with sodium hydroxide based on the equation shown in the attached picture.
It is clear that the ration between the benzoic acid and the sodium hydroxide is 1:1 in this reaction.
So, to answer this question, we will calculate the number of moles of sodium hydroxide used, equate it to the number of moles of benzoic acid and then calculate the mass of the calculated number of moles.
molarity = number of moles of solute / liter of solvent
0.1 = number of moles of sodium hydroxide / 0.02 liters
number of moles of sodium hydroxide = 0.002 moles
Therefore, number of moles of benzoic acid is also 0.002 moles
molar mass of benzoic acid = <span>122.12 grams
Therefore, the required mass of benzoic acid = 0.002 x </span><span>122.12
= 0.2444 moles</span>
Answer:
Atom, cell, dust particle, ant, ping pong ball
Explanation:
Firstly, atoms make up all matter, including each of the items on that list. The only things smaller than atoms are the parts of the atom itself, protons, neutrons and electrons. Because none of those are on that list, atoms have to be the smallest. Next smallest is the cell. Cells are made up of atoms, but they also in part make up dust. You can see a dust particle with the naked eye, but in order to see a cell you must use a microscope. Thus, cells are smaller than dust particles. Next is an ant. Obviously, an ant is bigger than a speck of dust, and is made up of cells and atoms. Lastly all you have is the ping pong ball, which is much larger than the rest of the items. Hope this helps!
Answer:
The correct option is;
A) The water molecules group together in clumps.
Explanation:
To answer the question, we look at each option as follows
A) The water molecules group together in clumps
This does not aid dissolution of compounds as clumping excludes non polar molecules, making them less soluble.
B) The partial negative oxygen atom end of the water molecule surround cations.
When an ionic compound such as NaCl is dissolved in water, the oxygen atoms surround the positive Na⁺ cations in the solution.
C) The partial positive hydrogen atom end of the water molecule surround anions
When the ionic NaCl compound is dissolved in water, the hydrogen atoms surround the negative Cl⁻ anions in the solution.
D) The water molecules also dissolve nonelectrolytes by creating a hydration sphere around the molecule.
Water is able to dissolve nonelectrolytes by creating an hydration sphere or hydration shell around the molecule.
Answer : The mass of the water molecule is 4.5 times greater than the mass of the helium atom.
Explanation :
Assumption : The number of water molecules is equal to the number of helium atoms
Given : The mass of water = 4.5 × The mass of helium ........(1)
The mass of Water = Mass of 1 water molecule × Number of water molecule
The mass of Helium = Mass of 1 helium atom × Number of helium atom
Now these two masses expression put in the equation (1), we get
Mass of 1 water molecule × Number of water molecule = 4.5 × Mass of 1 helium atom × Number of helium atom
As per assumption, the number of water molecules is equal to the number of helium atoms. The relation between the mass of water molecule and the mass of helium atom is,
Mass of water molecule = 4.5 × Mass of helium atom
Therefore, the mass of the water molecule is 4.5 times greater than the mass of the helium atom.
