FIRST PERIODICAL EXAM GRADE 7 NAME: SCORE: YEAR AND SECTION: DATE: I. MULTIPLE CHOICE. Circle the letter of the correct answer. 1. What is the set of procedures that can be used to explain and predict events or phenomena? A. Scientific discovery B. Scientific method C. Scientific notation D. Scientific thinking 2. Which of the following pairs of elements make up the salt compound? A. chlorine and oxygen B. oxygen and hydrogen C. sodium and chlorine D. sodium and hydrogen 3. What
Premium Education High school College
Electrolysis a) Electrolysis is the decomposition of a substance to give simpler substances. The substance being electrolysed has to be an ionic compound. b) The substance being decomposed is called the electrolyte. c) In electrolysis the electric current enters and leaves the electrolyte by conducting rods called electrodes. The positive electrode is called the anode and the negative electrode is called the cathode. d) For electrolysis to occur the electrolyte must be in liquid form so that
Premium Sodium chloride Hydrogen Electrolysis
solution? (A: 1.5g) 12. Vinegar is a solution of acetic acid. What is the molarity of the solution produced when 125g of acetic acid (C2H4O2) is dissolved in sufficient water to prepare 1.50 L of solution? (A: 1.39M) 13. How many grams of bromine‚ Br2‚ are needed to prepare 0.500 L of a 0.0100M solution in water?
Premium Water Concentration
In 1817 Johann Dobereiner noticed that the atomic weight of strontium fell midway between the weights of calcium and barium‚ elements possessing similar chemical properties. In 1829‚ after discovering the halogen triad composed of chlorine‚ bromine‚ and iodine and the alkali metal triad of lithium‚ sodium and potassium he proposed that nature contained triads of elements the middle element had properties that were an average of the other two members when ordered by the atomic weight (the Law
Free Periodic table Chemical element Chemistry
ROLE OF YOUTH IN OZONE LAYER PROTECTION Ozone layer plays a vital role in protecting animals‚ human beings and plants from ultraviolet radiation. Ozone layer is destroyed by a group of manufactured or human made chemicals such as chlorine bromine. These chemicals are called "ozone-depleting substances". Ozone layer is destroyed by some natural’s ways and some humane made activities. A single molecule of chlorine can break apart thousands of molecules of ozone. Chlorofluorocarbons the most widely
Premium Ozone depletion Ozone depletion
G. K: 1. Where did Aurangzeb die? (a) Ahmed ;Nagar‚(b) Allahabad‚(c)Aurangabad‚(d) Lahore. 2. The President of India can proclaim National Emergency- (a) On the advice of the Council of Ministers headed by the Primie Ministers‚(b) On the advice of the Speaker‚(c) On the advice of theLeader of the rulling party or set of parties in power‚ (d) At his own discretion. 3. Money bill has been difined by the constitution under Article_ (a) 109‚(b) 110‚(c)111‚(d) Both B and C. 4. The 93rd Constitutional
Premium Mohandas Karamchand Gandhi Salt Satyagraha India
2. (i) iodide has been converted to iodine (1) (with correct use and spelling of iodide and iodine) The 1st experiment shows that bromine is more reactive than iodine (1) The 2nd experiment shows that chlorine is more reactive than bromine (1) Accept 1 mark for 2nd and 3rd marking points if the correct reactivity order of chlorine > bromine > iodine has been stated. 3 (ii) Br2 + 2I– 2Br– + I2 (1) 1 [4]
Free Atom Electron Covalent bond
[pic] Contents |PART I PLANET EARTH | |Chapter 1 Fundamentals of chemistry | | |The scientific method |1 | |Kinetic theory of matter
Free Atom Electron Electric charge
Table of content 1 Introduction: 2 1.1 Objectives: 3 2 Manager of Marketing and Customer Service in the partnership Uzdrowisko Iwonicz S.A.: 3 2.1 Ideal model of manager: 4 2.2 Key responsibilities of Marketing and Consumer Service Manager: 5 2.3 Typical working day: 5 3 Marketing and Customer Service organization structure: 6 4 Key factors affecting good team work: 7 5 Conclusion: 7 6 Bibliography: 8 Balon Sandra sab39@aber.ac.uk Assignment Brief: ‘Interview with a Manager’
Premium Customer Customer service Sales
uncontrollable environmental factors. Introduction An alkyl halide or haloalkane is composed of hydrocarbons with a halogen attached to a sp3-hybridized carbon. It resembles an alkane with a halogen attached to it. Halogens are fluorine‚ chlorine‚ bromine‚ and iodine. Any of these halogens seen to be attached to an alkane‚ could then be identified as alkyl halides. They are generally polar because of the electronegativity difference of carbon (2.5) with the halogen (2.5-4.0). However‚ most alkyl halides
Premium Chlorine Hydrochloric acid Alkene