Answer:
[α] = -77.5° / 
Explanation:
Given;
Mass of optically pure substance in the solution = 10 g
Volume of water = 500 mL
Length of the polarimeter, l = 20 cm = 20 × 0.1 dm = 2 dm
measured rotation = - 3.10°
Now,
The specific rotation ( [α] ) is given as:
[α] = 
here,
α is the measured rotation = -3.10°
c is the concentration
or
c = 
or
c = 
or
c = 0.02 g/mL
on substituting the values, we get
[α] = 
or
[α] = -77.5° / 
Answer:
Sodium has a mass number of 23amu. Since sodium has 11 protons, the number of neutrons must be 23 – 11 = 12 neutrons.
Explanation:
The mass number is given at the top left of the elements symbol, for example, sodium has a mass number of 23.
Sodium (Na) square from the periodic table. The mass number (23) is top-left. The atomic number (11) is bottom-left.
We know that the atomic number of sodium is 11. This tells us that sodium has 11 protons and because it is neutral it has 11 electrons.
The mass number of an element tells us the number of protons AND neutrons in an atom (the two particles that have a measurable mass).
Sodium has a mass number of 23amu. Since sodium has 11 protons, the number of neutrons must be 23 – 11 = 12 neutrons.
So we know the number of moles of each compound. If we need to know the concentration we must know the number of moles that the compounds react with...
Answer:
The answer is the explanation.
Explanation:
The acetic acid, CH3COOH, reacts with calcium hydroxide, Ca(OH)2, producing acetate ion, CH3COO- and water as follows:
2CH3COOH + Ca(OH)2 → 2CH3COO- + 2H2O + Ca²⁺
That means the moles of acetic acid decrease whereas the moles of acetate ion are increased. The ratio of [CH3COOH] / [CH3COO-] is different.
As a base is added, the concentration of H3O+ decreases increasing the pH.
That means:
<em>TRUE </em> A. The number of moles of CH3COOH will decrease.
<em>FALSE</em> B. The number of moles of CH3COO- will decrease.
<em>TRUE </em>C. The equilibrium concentration of H3O will decrease.
<em>FALSE </em>D. The pH will decrease.
<em>FALSE</em> E. The ratio of [CH3COOH] / [CH3COO-] will remain the same.
Answer:
The car is carrying a volume of air that is moving at 80 mph relative to the ground. But inside the car itself, the air not moving very much. If you take the windshield out and drive a 80 mph you will smash the fly onto the back window.
Explanation:
.