Answer:
d = 0.9 g/L
Explanation:
Given data:
Number of moles = 1 mol
Volume = 24.2 L
Temperature = 298 K
Pressure = 101.3 Kpa (101.3/101 = 1 atm)
Density of sample = ?
Solution:
PV = nRT (1)
n = number of moles
number of moles = mass/molar mass
n = m/M
Now we will put the n= m/M in equation 1.
PV = m/M RT (2)
d = m/v
PM = m/v RT ( by rearranging the equation 2)
PM = dRT
d = PM/RT
The molar mass of neon is = 20.1798 g/mol
d = 1 atm × 20.1798 g/mol / 0.0821 atm. L/mol.K × 273K
d = 20.1798 g/22.413 L
d = 0.9 g/L
Yes. As long as the ratio of solute and solvent is same for both solution, the solution has the same concentration. for example, solution A has 2 ml of water, and 1 ml of sucrose. Solution B has 4ml of water and 2ml of sucrose. Both has a ratio of water to sucrose by 2 : 1. they have the same concentration of 50% sucrose.
Answer:
froth flotation is a technique commonly used in the mining industry. In this technique, particles of interest are physically separated from a liquid phase as a result of differences in the ability of air bubbles to selectively adhere to the surface of the particles, based upon their hydrophobicity.
Explanation:
Froth floatation method is commonly used to concentrate sulphide ore such as galena (PbS), zinc blende (ZnS) etc. (ii) In this method, the metaalic ore particles which are perferentially wetted by oil can be separated from gangue. (iii) In this method, the crushed ore is suspended in water and mixed with frothing agent such as pine oil, eucalyptus oil etc. (iv) A small quantity of sodium ethyl xanthate which act as a collector is also added. (v) A froth is generated by blowing air through this mixture. (vi) The collector molecules attach to the ore particles and make them water repellent. (vii) As a result, ore parrticles, wetted by the oil, rise to the surface along with the froth. (viii) The froth is skimmed off and dried to recover the concentration ore. (ix) The gangue particles that are preferentially wetted by water settle at the bottom.
The only true answer is A.
products are on the right side of the reaction
products and reactants don't necessarily have same physical or chemical properties
It is the reactants that <span>are the atoms, molecules, or compounds that participate in the reaction.</span>
PH of a solution will be <span>higher than 7
</span>
Ammonium cyanide is a salt formed by hydrogen cyanide and ammonia. Ammonia is a weak base and hydrogen cyanide is a weak acid.
NH₄CN + H₂O ⇒ NH₃ + HCN
NH₄⁺ + H₂O -----> H₃O⁺ + NH₃
CN⁻ + H₂O -----> HCN + OH⁻
Although both compounds are weak electrolytes, NH₃ is somewhat stronger base than HCN is a strong acid, so the solution reacts alkaline. We can prove this using Ka and Kb values:
Ka(HCN) = 4.9 x × 10⁻¹⁰
Kb(NH₃) = 1.8 × 10⁻⁵<span>
Kw= </span>1.0 × 10⁻¹⁴
Let's first calculate Ka for NH₄⁺:
Ka(NH₄⁺) x Kb(NH₃<span>) = pKw
</span>Ka(NH₄⁺) = Kw/Kb(NH₃) = 5.6 x 10⁻¹⁰
Then, Kb for CN⁻:
Kb(CN⁻) x Ka(HCN) = pKw
Kb(CN⁻) = Kw/Ka(HCN) = 2 x 10⁻⁵
From this, we can see that the acid constant NH4⁺ is much lower than the base constant of CN⁻, which will say that the solution of NH₄CN will react slightly alkaline because of the higher presence of hydroxyl ions in solution.
