Twent - Study guides, Class notes & Summaries

2 © OCR 2023 Solid sphere Dalton’s model Modern model 1 Scientists use models to represent atoms. These models have changed over time. Dalton’s model and a modern model of an atom are shown in the diagrams. (a) Give two differences between the modern model and Dalton’s model. 1 ................................................................................................................................................ ................................................................

2 © OCR 2023 Incomplete combustion of fossil fuels 1 The combustion of fossil fuels for energy produces harmful substances. (a) (i) Draw lines to connect each harmful substance with the description of its major source. Harmful substance Major source [2] (ii) Explain one problem caused by increased amounts of sulfur dioxide in the atmosphere. ........................................................................................................................................... ....

2 © OCR 2023 ring Gamma rays Microwave Radio Visible X-rays Ultraviolet 1 (a) Which two statements about electromagnetic radiation are true? Tick () two boxes. All electromagnetic radiation is ionising. All electromagnetic radiation travels through space at the same speed. Only very hot bodies emit electromagnetic radiation. Our eyes can only detect a limited range of electromagnetic frequencies. Gamma rays are used for satellite communications. [2] (b) (i) Complete the table by sh...

2 © OCR 2023 1 A student investigates the path of light passing through a triangular glass prism. A narrow beam of white light is directed at the prism with an angle of incidence equal to 40°. The student observes a spectrum of different coloured light. Narrow beam of white light Spectrum of coloured light The two-dimensional diagram shows a narrow beam of white light directed at the side of a prism. A line showing the path of a ray of blue light passing through the prism is pa...

2 © OCR 2023 Part A Eyepiece lens Part B Objective lens Part C Stage 1 A doctor uses a light microscope to look at the chromosomes in human body cells. (a) The microscope is shown in the diagram. Fine focus Part A Part B Part C Coarse focus Mirror (i) Draw lines to connect each part of the microscope with its correct name. Part Name [1] (ii) The doctor uses steps A to D to look at the cells on a slide. The steps are not in the correct order. A Turn the coarse focus until the i...

2 © OCR 2023 Microwave Sun beds Ultraviolet Cooking food X-rays Sterilising surgical instruments Gamma rays Looking for broken bones 1 Draw lines to connect each part of the electromagnetic spectrum to its use. Electromagnetic spectrum Use [3] 13 © OCR 2023 Turn over BLANK PAGE PLEASE DO NOT WRITE ON THIS PAGE 4 © OCR 2023 2 Sam is making measurements to calculate the density of a rubber bung. (a) Which piece of apparatus does Sam use to measure the mass of the bung? Tick () ...

GCSE Chemisty B Twenty First Century Science J258/04: Depth in Chemistry (Higher Tier) General Certificate of Secondary Education Mark Scheme for June 2023

2 © OCR 2023 1 (a) (i) Complete the table to compare cellular aerobic and anaerobic respiration in humans. Tick () the correct boxes in each row. [3] (ii) Which statement about respiration is correct? Tick () one box. Aerobic respiration produces more ATP than anaerobic respiration. Anaerobic respiration produces more ATP than aerobic respiration. Both aerobic and anaerobic respiration produce the same amount of ATP. Neither aerobic or anaerobic respiration produces ATP. [1] (b) H...

2 © OCR 2023 Tissue B is made of unspecialized cells Meristem Tissue A transports water from the plant’s roots 1 A scientist cuts a thin slice from a plant stem, as shown in Fig. 1.1. The slice of stem contains three different tissues. Fig. 1.1 B Plant stem Tissue C (a) Draw lines to connect the description of each tissue with its correct name. One has been done for you. Description Name [1] Capillary Tissue Tissue A Xylem Tissue C transports sugar from the plant’s ...