New research shows that a red food colouring with an R value of 0.62 (when a particular solvent and temperature are used) could be dangerous to certain people. Samples of food colouring from two different red sweets were collected and the chromatogram bolow was produced. For each of the sweets, state and explain whether or not you would recommend that the sweets are taken off the market based on this research,

Which of the following pairs of elements belong to the same groupa. h and he b. li and bec. c and pb d. ga and ge

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)

Which of the following are good traits of a hypothesis? it will be able to be testedit can predict an outcomeit will explain the observationsall of these