Answer: 7.71 + 4.31 + 1.7 + 4.00141=
17.72141
7.71 x 4.31 x 1.7 x 4.00141= 226.04433255
Explanation:
(i) 7.71 + 4.31 + 1.7 + 4.00141
= 7.71000+4.31000+1.70000+ 4.00141 [make like decimals]
= 17.72141 [By adding the corresponding places ]
(ii) 7.71 x 4.31 x 1.7 x 4.00141 =( 7.71 x 4.31) x 1.7 x 4.00141
= 33.2301 x 1.7 x 4.00141
= (33.2301 x 1.7) x 4.00141
= 56.49117 x 4.00141
= ( 56.49117 x 4.00141 )
= 226.04433255
Hence, 7.71 + 4.31 + 1.7 + 4.00141=
17.72141
7.71 x 4.31 x 1.7 x 4.00141= 226.04433255
Answer:
pH of the final solution = 9.15
Explanation:
Equation of the reaction: HCl + NH₃ ----> NH₄Cl
Number of moles of NH₃ = molarity * volume (L)
= 0.4 M * (300/1000) * 1 L = 0.12 moles
Number of moles of HCl = molarity * volume (L)
= 0.3 M * (175/1000) * 1 L = 0.0525 moles
Since all he acid is used up in the reaction, number of moles of acid used up equals number of moles of NH₄Cl produced
Number moles of NH₄Cl produced = 0.0525 moles
Number of moles of base left unreacted = 0.12 - 0.0525 = 0.0675
pOH = pKb + log([salt]/[base])
pKb = -logKb
pOH = -log (1.8 * 10⁻⁵) + log (0.0525/0.06755)
pOh = 4.744 + 0.109
pOH = 4.853
pH = 14 - pOH
pH = 14 - 4.853
pH = 9.15
Therefore, pH of the final solution = 9.15
Answer:
90.5mL is the volume of the gas at STP
Explanation:
It is possible to find volume of a gas when conditions of temperature and pressure change using combined gas law:

Where P is pressure, V is volume and T is absolute temperature. 1 is initial conditions and 2 final conditions.
If initial conditions are 1.08atm, 80.0mL and absolute temperature is (-12.5°C + 273.15) = 260.65K.
And STP are 1atm of pressure and 273.15K of absolute temperature. Replacing:

V₂ = <em>90.5mL is the volume of the gas at STP</em>
The atomic number is the numbers of protons