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1. Explain Ni and Fe enrichment in olivine-rich layers in mafic and ultramafic intrusions. 2. Show why hydrothermal ore deposits in an area occur as stockwork systems and in brittle structures
What mass of silver nitrate, AgNO₃₍ₐᵩ₎, is needed to react with solid copper to produce 525 kg of copper (II) nitrate, Cu(NO₃)₂₍ₐᵩ₎? Cu₍ₛ₎ + 2AgNO₃₍ₐᵩ₎ --> 2Ag₍ₛ₎ + Cu(NO₃)₂₍ₐᵩ₎
(a) In the standardization of hydrochloric acid using sodium tetraborate, a student performs the following steps: (i)A certain quantity of sodium tetraborate was weighed accurately and placed in a 250 mL volumetric flask. (ii) 25 mL of this stock solution was then titrated with the hydrochloric acid using bromocresol green as an indicator.
If the average titre value obtained for this titration was 10.5 mL and the concentration of hydrochloric acid was determined to be 0.4 M, calculate the initial mass of sodium tetraborate that was weighed out. Comment on why phenolphthalein is not an appropriate indicator for this titration.
(b) A sample contains 5.88 % by mass of the compound: C6H3Cl(CO2H)2.
(i)What mass of sample will be required to react completely with 3.924 g of sodium hydroxide?
(ii)Give the repeating unit when the compound, C6H3Cl(CO2H)2, reacts with C4H8(CH2NH2)2.
A 0.410 L sample of argon is collected at 45 oC. If the temperature of the sample is increased to 75 oC, what volume will the gas occupy? Assume that the pressure and amount of gas are kept constant through the heating process.
A gas contains a mixture of nitrogen, helium, and oxygen at a total of 150 kPa. The pressure of the oxygen is 100 kPa, and the pressure of nitrogen is 34 kPa. What is the pressure of the helium?
A is placed in a cylinder and has a pressure of 33.3 kPa, a temperature of 25 oC, and a volume of 0.345 L. The pressure of the gas is increased to 40 kPa, and the volume is increased to 0.50 L. What is the temperature of the gas?
Assume that a gas fills a 0.55 L container at 1.0 kPa. If the volume of the gas is increased to 4.0 L, what will be the pressure of the gas?
(a)In the standardization of hydrochloric acid using sodium tetraborate, a student performs the following steps: (i) A certain quantity of sodium tetraborate was weighed accurately and placed in a 250 mL volumetric flask. (ii) 25 mL of this stock solution was then titrated with the hydrochloric acid using bromocresol green as an indicator. If the average titre value obtained for this titration was 10.5 mL and the concentration of hydrochloric acid was determined to be 0.4 M, calculate the initial mass of sodium tetraborate that was weighed out. Comment on why phenolphthalein is not an appropriate indicator for this titration
(b)A sample contains 5.88 % by mass of the compound: C6H3Cl(CO2H)2. (i) What mass of sample will be required to react completely with 3.924 g of sodium hydroxide?
(ii) Give the repeating unit when the compound, C6H3Cl(CO2H)2, reacts with C4H8(CH2NH2)2.
Calculate the mass of iodine that must be
reacted with excess phosphorus to produce
5.00 g of phosphorus(III) iodide according to
the equation below.
2P+3I2 → 2PI3
CH3NH2 + H2O <-> CH3NH3+ + OH-
Ka = 2.33x10^-11
Given the CH3NH2 concentration is 1.5M, what is the equilibrium concentration of Ch3NH2, CH3NH3+, OH-?
