A student performed an experiment in which they reacted 50cm3 of 0.300mol dm-3 sodium thiosulfate with 5.0cm3 of 2.000 dm-3 hydrochloric acid. They are investigating the affect of changing conditions on the rate of reaction. Which of the following concentrations of hydrochloric acid would result in the slowest rate of reaction?

Consider two reactions, one that is second order and one that is third order. Which best describes the effect on the reaction rates by DECREASING the concentration of all reactants?Select answer from the options below

10 A large excess of marble chips is reacted with 25 cm 3 of 1.0 mol dm –3 hydrochloric acid at 40 C.How is the result different when the reaction is repeated with 60 cm 3 of 0.5 mol dm –3 hydrochloricacid at 40 C?A The reaction is faster and more of the products are made when the reaction is complete.B The reaction is faster and less of the products are made when the reaction is complete.C The reaction is slower and more of the products are made when the reaction is complete.D The reaction is slower and less of the products are made when the reaction is complete.

3. A student conducts an experiment where she reacts a lump of zinc (Zn) with hydrochloric acid (HCl). The balanced equation below represents the reaction.     Zn +  2HCl  →  H₂  +  ZnCl₂   Which set of reaction conditions will produce H₂ at the fastest rate?*1.0 g of powdered Zn in 50mL of 1.0 M HCl at 20°Ca 1.0 g lump of Zn in 50mL of 0.5 M HCl at 30°C1.0 g of powdered Zn in 50mL of 1.0 M HCl at 30°Ca 1.0 g lump of Zn in 50mL of 0.5 M HCl at 20°C

You are investigating how the rate of reaction depends upon the concentration of hydrochloric acid when it is reacted with sodium thiosulfate in a small glass beaker. Which reagent in this experiment poses the greatest hazard?sodium thiosulfatehydrochloric acid

A student is investigating the reaction between nitric acid and calcium carbonate under different conditions. Which of the following changes would not cause the rate of the chemical reaction to increase?