Answer:
C. Scientists accepted the model at first but later rejected it.
Explanation:
Scientists accepted the model at first because it explained the hydrogen emission spectrum.
However, with the development of quantum mechanics, scientists had to modify the model (not reject it).
Electrons still had specific energies, but they no longer travelled in fixed orbits.
Instead, electrons had a probability of being found in a given region of space.
Answer: False
Explanation: Electrolyte are good conductors of electricity because they contain ions which are able to move about
Answer: It is a gas
Explanation:
The most unique thing about nitric oxide being a neurotransmitter is that it is the only neurotransmitter which is in gaseous form.
Nitric oxide is small gaseous molecules which is synthesized by the de novo process in the neuronal tissue.
It can diffuse by plasma membrane.
It diffuses out of the postsynaptic neurons and acts on the neighboring neurons and presynaptic terminals to assist the generation of the Long Term potentiation.
Answer:
(Ar) 4s2
Explanation:
How many numbers in tje outershell etc calcium atomivc no20
Answer: 51 grams
Explanation:
Ammonia is a gas with a chemical formula of NH3.
Given that,
Amount of moles of NH3 (n) = ?
Volume of NH3 (v) = 200mL
since the standard unit of volume is liters, convert 200mL to liters
(If 1000mL = 1L
200mL = 200/1000 = 0.2L)
Concentration of NH3 (c) = 1.5M
Since concentration (c) is obtained by dividing the amount of solute dissolved by the volume of solvent, hence
c = n / v
Make n the subject formula
n = c x v
n = 1.50M x 0.2L
n = 3 moles
Now, calculate the mass of ammonia
Amount of moles of NH3 (n) = 3
Mass of NH3 in grams = ?
For molar mass of NH3, use the atomic masses:
N = 14g; H = 1g
NH3 = 14g + (1g x 3)
= 14g + 3g
= 17g/mol
Since, n = mass in grams / molar mass
3 moles = m / 17g/mol
m = 3 moles x 17g/mol
m = 51 grams
Thus, 51 grams of ammonia was dissolved in the solution.
