At room temperature, one of these compounds is a solid and one is a liquid: SiO, or PBr3.

Sodium hydrogen sulfate is used as a cleaning agent and as a flux (a substance that promotes the fusing of metals and prevents the formation of oxides). One of the ways in which sodium hydrogen sulfate is manufactured is by reacting sodium dichromate, Na2Cr2O7, with sulfuric acid. This process also forms water and chromium(VI) oxide, CrO3. Write a balanced equation for this reaction. (You do not need to include states.) How many kilograms of sodium dichromate, Na2Cr2O7, are necessary to produce 130.4 kg of sodium hydrogen sulfate? How many kilograms of chromium(VI) oxide are formed when 130.4 kg of sodium hydrogen sulfate is made? What is the minimum volume of 18.0 M H2SO4 solution necessary to react with 874.0 kg of sodium dichromate? What is the maximum mass of sodium hydrogen sulfate, NaHSO4, that can be formed from the reaction of 874.0 kg of sodium dichromate with 400.0 L of 18.0 M H2SO4?

Because carbon and silicon are both elements in group 14 on the periodic table, we expect them to react with other elements in similar ways. To some extent, they do, but in some cases, carbon and silicon compounds that seem to have analogous structures have very different chemical characteristics. For example, carbon tetrachloride, CCl4, is very stable in the presence of water, but silicon tetrachloride, SiCl4, reacts quickly with water. The unbalanced equation for this reaction is SiCl4 + H2O → Si(OH)4 + HCl Balance this equation. Write a conversion factor that could be used to convert between moles of SiCl4 and moles of H2O. How many moles of SiCl4 react with 24 moles of water? Write a conversion factor that could be used to convert between moles of Si(OH)4 and moles of water. How many moles of Si(OH)4 form when 4.01 moles of H2O react with an excess of SiCl4?

Modern commercial airliners are largely made of aluminum, a light and strong metal. But the fact that aluminum is cheap enough that airplanes can be made out of it is a bit of historical luck. Before the discovery of the Hall-Héroult process in 1886, aluminum was as rare and expensive as gold. What would happen if airplanes had to be made of steel? The fuselage of the Boeing 777, which can carry 305 passengers, is approximately a hollow aluminum cylinder without ends, 64.0 m long, 6.2 m wide, and 2.5 mm thick (see sketch at right). The fuselage of an airplane Suppose this fuselage was made of steel (density 7.87 g/cm³) instead of aluminum (density 2.70 g/cm³), and let's say the average passenger has a mass of 81 kg. We'll also assume the engines can't lift any greater mass than they already do. Calculate the number of passengers that the Boeing 777 could carry if its fuselage was made of steel. X Ś

1. More than 2000 years ago human cultures figured out a way to produce iron metal from rocks containing iron ores. This iron could be worked by a blacksmith (repeated heating and hammering) to make iron metal pure enough for creating useful tools (even Samurai swords). This direct heating technique was common up until about 200 years ago when people found a better way to obtain iron metal. When hematite, Fe2O3(s), is strongly heated in a blast furnace in the presence of charcoal (carbon), pure iron metal is obtained. Fe2O3() 2 Fe(s) + 3/2 O2 (g) (1) C(s) + O2 (g) → CO2(g) (2) When reaction 1 is coupled to reaction 2, overall chemical equation is Fe2O3() + 3/2 C() 3/2 CO2(g) + 2 Fee) Use the thermodynamic data given below for the following calculations: AG¡ (kJ/mol) | 4H¡ (kJ/mol) | S (J/mol-K) Fe2O3(s) -742.2 -824.2 87.40 Fes) 27.28 CO2(8) -394.36 -393.51 213.74 C (6) 5.74 O2 (2) 205.14 a) Calculate the standard Gibb's free energy change for reaction 1 b) Calculate the standard Gibb’s…

The titanium chloride then reacts with liquid magnesium at 900°C to givetitanium and magnesium chloride (MgCl2). Write a balanced chemicalequation for this step in the refining of titanium.

What mass of Cu(IO3)2 can be formed from 0.650 g of CuSO4 · 5H2O? What mass of KIO3 is needed to convert the copper in 0.2750 g of CUSO4 - 5H2O to Cu(IO3)2?

Write the full electron configuration of Si, Si+4 and Si-4. How many valence electrons are in each of the 3 Si atoms?

Magnesium metal (Mg(s)) burns brightly in oxygen gas (O2(g)) to produce a whitish-grey powder, magnesium oxide (MgO(s)). Write a balanced equation for this reaction.

Cr(s) + O2(g)→ Cr,O3(s)