GCSE CHEMISTRY PAPER 1 QUESTIONS WITH CORRECT ANSWERS.

GCSE CHEMISTRY PAPER 1 QUESTIONS WITH CORRECT ANSWERS. Calculate the surface area of a nanoparticle of zinc oxide. Give your answer in standard form. - Answer-82nm x 82nm x 6(faces of a cube) =40,344 = 4.0344 x 10^4 Complete the sentence: In the modern periodic table, the elements are arranged in order of ___________ - Answer-Their atomic number. Complete the word equation for the reaction: calcium hydroxide + ___________acid → calcium chloride + __________________ - Answer-calcium hydroxide + hydrochloric acid → calcium chloride + water Define mass number - Answer-The total number of protons and neutrons in a nucleus. Describe what you would see when sodium reacts with chlorine. - Answer-A bright yellow light A Lot of Heat (energy) / Temperature increase Produces fumes of sodium Draw the dot and cross diagram for NH3 - Answer- Evaluate the use of the materials to make badminton racket frames. Refer to Question Paper - Page 9 - Answer- explain why the reaction between ammonia and oxygen is exothermic. The overall energy change is -1272 - Answer-The overall energy change is negative so energy has been lost meaning the reaction is exothermic. Suggest one reason why it costs less to use nanoparticles rather than fine particles in suncreams. - Answer-Nanoparticles have longer-lasting antibacterial properties than bigger particles of silver. Suggest two control variables used in this investigation. Refer to Question paper - Page 17 - Answer-1. The Copper electrode