UTTAM SCHOOL FOR GIRLS PSA WORKSHEET: SCIENCE GRADE: VI

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Cornelia Pierce
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1 UTTAM SCHOOL FOR GIRLS PSA WORKSHEET: SCIENCE GRADE: VI PASSAGE 1: EVERYDAY COMPOUNDS OR POISON? All elements found on the periodic table have certain distinct properties. Elements are single types of atoms, while atoms are the fundamental building blocks of all matter. Gold, for instance, is a soft, naturally occurring metal known for being beautiful and desired. Oxygen is a necessary and naturally occurring element. When the atoms of a specific substance are regrouped, a new substance is formed with often vastly different properties from the original substance. For example, when an oxygen atom and two hydrogen atoms come together they form water, which is essential to life. Occasionally something completely harmless can become dangerous or lethal when its molecules are regrouped. Common table salt (sodium chloride) is an interesting chemical compound because, when you separate its elements sodium and chlorine you are left with something quite different from the edible seasoning known as salt. Sodium requires great care when being handled. Chlorine is an extremely dangerous substance used primarily as a cleaning agent in swimming pools to render them sanitary. Chlorine is a toxic gas which reacts with the mucous of the lungs and creates a potentially lethal compound known as hydrochloric acid. During World War I, chlorine gas was used by Germany as a chemical weapon. Another, perhaps more familiar, example of atoms being regrouped to form a different compound is carbon monoxide and carbon dioxide. The scientific difference between the two compounds is the number of oxygen atoms bonded with the carbon atom. Carbon monoxide occurs naturally in animal metabolism, plant photosynthesis, volcano eruption, forest fires and other combustion. It also comes from manmade processes like operating a stove. People who directly inhale enough carbon monoxide will lose consciousness and eventually die. Carbon dioxide, on the other hand, occurs naturally in the atmosphere and is produced is through the breathing processes of humans and animals. It is emitted in the burning of fossil fuels. Carbon dioxide can be dangerous to humans when inhaled in certain quantities. Slight chemical changes can radically modify the characteristics of a compound, and we don t have to look to radically different elements to find enormous differences. Sometimes only a small difference in chemical composition results in a very important alteration. Information source:

2 1. What happens when the atoms of a substance are regrouped? a) gold becomes malleable b) the atoms break apart and disappear c) a new substance is formed d) the substance stays the same 2. The creation of carbon monoxide is an effect. What is one cause? a) the regrouping of the atoms in table salt b) the burning of fossil fuels c) cleaning swimming pools d) operating a stove 3. Table salt can be separated into sodium and chlorine. Sodium is explosive. Chlorine is a gas that can kill people. What can be concluded from the statements above? a) A harmful compound can become harmless when its elements are separated. b) A harmless compound can become harmful when its elements are separated. c) Breaking a compound into its separate elements has no noticeable effects. d) Breaking a compound into its separate elements can create carbon dioxide. 4. Based on the information in the passage, what is true of gases? a) Some, but not all, gases are harmful to humans. b) Any gas with carbon in it is not harmful to humans. c) All gases are harmful to humans. d) No gases are harmful to humans. 5. An example of compound discussed in the passage is: a) Gold b) Water c) Carbon d) Oxygen 6. The passage is mainly about: a) Germany s use of chlorine in World War I as a chemical weapon b) Elements and compounds c) the similarities and differences between carbon dioxide and carbon monoxide d) changes in chemical compounds and the effects of those changes

3 7. Read the following sentences: When the atoms of a specific substance are regrouped, a new substance is formed with often vastly different properties from the original substance. What does the word properties mean above? a) extremely large amounts b) places where experiments are done c) qualities or characteristics d) elements or compounds 8. Choose the example of an element from the passage: a) Carbon dioxide b) Hydrochloric acid c) Sodium chloride d) Oxygen 9. One familiar example of regrouping of atoms to form a different compound is: a) Hydrochloric acid b) Sodium chloride c) Water d) Carbon monoxide 10. The gases discussed in the passage are arranged in the increasing order of toxicity. Choose the correct option: a) Carbon dioxide< Carbon monoxide <chlorine b) Carbon dioxide< Carbon monoxide<chlorine c) Chlorine< Carbon dioxide< Carbon monoxide d) Carbon dioxide < Carbon monoxide< Chlorine

UTTAM SCHOOL FOR GIRLS PSA WORKSHEET: SCIENCE GRADE: PASSAGE 2: ELECTROMAGNETIC RADIATION What are we looking at when we look at objects? When you look at a basketball, what are you seeing?

4 UTTAM SCHOOL FOR GIRLS PSA WORKSHEET: SCIENCE GRADE: PASSAGE 2: ELECTROMAGNETIC RADIATION What are we looking at when we look at objects? When you look at a basketball, what are you seeing? There are many ways to think about how we perceive the information our eyes take in from the outside world. Science tells us that light is the reason we are able to see objects. And the light that allows us to see isn t just the stuff that comes from light bulbs in our homes and schools. Light is a form of electromagnetic radiation made of electromagnetic waves. So there are plenty of waves being expressed by the physical world that we simply don t get to see. On the electromagnetic spectrum, you will see that there are all different types and intensities of waves. The electromagnetic spectrum is organized in order of wavelength. There are different types of light, each with a different length of wave. Electromagnetic Radiation The portion of the spectrum that our eyes are sensitive to called visible light is smack dab in the middle of the spectrum. Many of the tools mankind has invented over time to harness the information contained within electromagnetic radiation are present in your home or school every day, including televisions and radios. Other tools like night-vision goggles are also examples of technology that gives us superhuman access to wave frequencies further toward the ends of the known spectrum. If it weren t for the way our eyes and brain are able to create comprehensible images from waves of visible light, it would be very difficult for us to understand the messages emitted by our physical universe.

5 1. What allows people to see objects? a) radio waves b) glass c) x-rays d) light 2. What does the author list in the passage? a) different types of electromagnetic spectrums b) different types of electromagnetic radiation c) scientists who study electromagnetic radiation d) the differences between radio waves and microwaves 3. We can think of electromagnetic waves as a kind of ongoing message being sent out by the universe. Humans are able to naturally access only a portion of this message. What information from the passage best supports this statement? a) Mankind has invented tools to harness the information contained within electromagnetic radiation. b) The waves emitted by our physical world make it possible for us to communicate over vast distances. c) Without light, we wouldn t be able to process the visible world. d) The human eye is only sensitive to a portion of the electromagnetic spectrum. 4. Based on the passage, what can be concluded about the ability of humans to see X rays and gamma rays? a) Humans cannot see X-rays and gamma rays. b) Humans can see X-rays and gamma rays. c) Humans can see X-rays but not gamma rays. d) Humans can see gamma rays but not X-rays. 5. What is the passage mainly about? a) why waves have different wavelengths b) electromagnetic waves and how humans utilize them c) different tools humans have invented to harness information d) gamma rays and x-rays

6 6. The wavelength of UV rays are more than that of: a) X- rays b) Micro waves c) Visible spectrum d) Gamma rays 7. The rays having highest energy are: a) Gamma rays b) Visible light c) Radio waves d) Micro- waves 8. Choose the correct pair: a) Gamma rays: highest energy b) Visible spectrum: 10-3 nm c) Radio waves: highest energy d) Radio waves: longest wavelength 9. The range of visible spectrum is: a) 750nm b) 380nm c) 370nm d) 10 3 nm 10. Identify the rays which lie between 10 3 nm to 10 6 nm: a) Micro waves b) Infra red c) Radio waves d) Visible light

Everyday Compound or Poison?

3 rd Year Form Chemistry Everyday Compound or Poison? All elements found on the periodic table have certain distinct properties. Elements are single types of atoms, while atoms are the fundamental building