Answer: -
3.151 M
Explanation: -
Let the volume of the solution be 1000 mL.
At 25.0 °C, Density = 1.260 g/ mL
Mass of the solution = Density x volume
= 1.260 g / mL x 1000 mL
= 1260 g
At 25.0 °C, the molarity = 3.179 M
Number of moles present per 1000 mL = 3.179 mol
Strength of the solution in g / mol
= 1260 g / 3.179 mol = 396.35 g / mol (at 25.0 °C)
Now at 50.0 °C
The density is 1.249 g/ mL
Mass of the solution = density x volume = 1.249 g / mL x 1000 mL
= 1249 g.
Number of moles present in 1249 g = Mass of the solution / Strength in g /mol
= 
= 3.151 moles.
So 3.151 moles is present in 1000 mL at 50.0 °C
Molarity at 50.0 °C = 3.151 M
Answer:
3 AU
Explanation:
The distance from the Earth to the Sun is known as 1 AU, or 1 Astronomical Unit. If an asteroid is three times this distance, it is 3 AU away.
Answer: Rate in terms of disappearance of
= ![-\frac{1d[NO]}{2dt}](https://tex.z-dn.net/?f=-%5Cfrac%7B1d%5BNO%5D%7D%7B2dt%7D)
Rate in terms of disappearance of
= ![-\frac{1d[Cl_2]}{1dt}](https://tex.z-dn.net/?f=-%5Cfrac%7B1d%5BCl_2%5D%7D%7B1dt%7D)
Rate in terms of appearance of
= ![\frac{1d[NOCl]}{2dt}](https://tex.z-dn.net/?f=%5Cfrac%7B1d%5BNOCl%5D%7D%7B2dt%7D)
Explanation:
Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.

The rate in terms of reactants is given as negative as the concentration of reactants is decreasing with time whereas the rate in terms of products is given as positive as the concentration of products is increasing with time.
Rate in terms of disappearance of = ![-\frac{1d[NO]}{2dt}](https://tex.z-dn.net/?f=-%5Cfrac%7B1d%5BNO%5D%7D%7B2dt%7D)
Rate in terms of disappearance of = ![-\frac{1d[Cl_2]}{1dt}](https://tex.z-dn.net/?f=-%5Cfrac%7B1d%5BCl_2%5D%7D%7B1dt%7D)
Rate in terms of appearance of
= ![+\frac{1d[NOCl]}{2dt}](https://tex.z-dn.net/?f=%2B%5Cfrac%7B1d%5BNOCl%5D%7D%7B2dt%7D)
1.3622052x10^6 you move the . 6 places to the left making it a positive 10^6
Answer:
pH = 3.49
Explanation:
We have a buffer system formed by a weak acid (HNO₂) and its conjugate base (NO₂⁻ coming from KNO₂). We can calculate the pH of a buffer ssytem using the Henderson-Hasselbach equation.
pH = pKa + log [base] / [acid]
pH = -log Ka + log [NO₂⁻] / [HNO₂]
pH = -log 4.50 × 10⁻⁴ + log 0.290 M / 0.210 M
pH = 3.49