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calculate number of zinc ions in 10g of zinc hydroxide
3000 J of heat is added to a system and 2500 J of work is done by the system. What is the change in internal energy of the system.
A sample of helium occupies 535 ml at 988 torr and 25°C. If the sample is transferred to a 1.05 L flask at 25°C, what will be the gas pressure in the flask?
The molality of 0.05 mol hcl in 5 litre solution at 4°c
The solubility product of lithium phosphate (Li3PO4) is 3.2 × 10-9 at 25° C. What is the molar concentration of Li+ ions in mol/L in an equilibrium mixture of lithium phosphate at 25° C?
Calculate the value of the ion product of PbCl2 (Ksp = 1.6 ×10-5) when 255 mL of 0.016 M KCl (aq) are added to 245 mL of 0.175M Pb(NO3)2.
2. The following data are measure for a mixture of volatile liquid M and N at 1.013 bar. T(°C) 78 75 70 70 75 80 XM 0.00 0.04 0.21 0.86 0.96 1.00 Ум 0.00 0.18 0.42 0.66 0.83 1.00 (a) Estimate the azeotropic composition. (b) Estimate the mole fraction range of liquid M for which pure liquid M will obtained. Briefly explain your answer. (c) Estimate the amount of liquid N in both phases if 0.08 g of liquid M and 0.02 g of liquid N were mixed at 72 °C. (d) If the mixture of XM= 0.96 heated at 74 °C, what is the composition of liquid Mand N in the last drop of liquid and in first vapor appear. (e) If the mixture in part (c) were heated, which liquid will be the distillate and residue?
The rate constant for the decomposition of a substance X is 6.2×10⁻³ s⁻¹. This reaction follows the first order kinetics. If the initial rate of decomposition of X is 3.1×10⁻⁴ Ms⁻¹, calculate the initial concentration of X. Also calculate the time required for 87% decomposition of X at ths temperature.
If a solid PQ have NaCl type structure is heated so that the ions along one body diagonal are lost and trivalent ions(R) enter interstitial sites to maintain the electrical neutrality so that the new empirical formula unit is PxQyRz(x,y,z are smallest possible integers). The values of x+y+z is [Q- form the lattice]
