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Questions in chemistry

[Done] If a jar of honey sits for a long time, sugar may crystallize in the jar. Describe two possible causes for the crystallization.

[Done] Suppose that you are given two unlabeled beakers. One beaker contains water, and the other beaker contains a solution of ethanol and water. How could you safely determine which beaker contains just water?

[Done] If a handsaw does the same amount of work on a log as a chainsaw does, which has more power? Why?

[Done] The total amount of _________ is the same before and after any transformation.

[Done] The rate law for a hypothetical reaction is given by: \[ \text{rate} = k [A][B] \] If the concentrations of \( A \) and \( B \) are both \( 0.020 \, \text{moles per liter} \) and \( k = 1.3 \times 10^{-1} \, \text{M}^{-1}\text{s}^{-1} \), what is the reaction rate?

[Done] Describe the steps involved in the fractional distillation of crude oil.

[Done] A student investigated the rate of reaction between sodium thiosulphate and dilute hydrochloric acid. - The student placed a conical flask over a cross on a piece of paper. - The student mixed the solutions in the flask. - The solution went cloudy. - The student timed how long it took until the cross could not be seen. The equation for the reaction is: \[ \text{Na}_2\text{S}_2\text{O}_3(aq) + 2\text{HCl}(aq) \rightarrow 2\text{NaCl}(aq) + \text{H}_2\text{O}(l) + \text{SO}_2(g) + \text{S}(s) \] Explain why the solution goes cloudy.

[Done] Thermosoftening polymers can be used to make plastic bottles and food packaging. 1) The reaction to produce polymers uses a catalyst. Why does the catalyst work for a long time before it needs replacing? 2) Thermosoftening polymers would not be suitable for packaging very hot food. Explain why in terms of their properties and structure.

[Done] Is glass biotic or abiotic?

[Done] The reaction described in Part A required 3.98 L of calcium chloride. What is the concentration of this calcium chloride solution?