North American International School Chemistry Semester 1 Exam 2025 PDF

**Semester 1 Exam CHEMISTRY January-2025** -------- **60** -------- **Name:.........................................................................** **Subject: Grade: \_\_\_\_\_\_\_\_\_\_ Class \_\_\_\_\_\_\_\_\_** Teacher: Miss Mona Shaaban, Mr. Mohammad Al Saadi, Miss Almas Nafees [**...

**Semester 1 Exam CHEMISTRY January-2025** -------- **60** -------- **Name:.........................................................................** **Subject: Grade: \_\_\_\_\_\_\_\_\_\_ Class \_\_\_\_\_\_\_\_\_** Teacher: Miss Mona Shaaban, Mr. Mohammad Al Saadi, Miss Almas Nafees [**Total no. of pages:** 18 ] [Time: 2 hours ] [Total Marks ] ***S.NO*** ***DOMAIN*** ***STANDARDS*** ***QUES*** ***SCORE*** ***F.A*** ***P.A*** ***N.A*** ---------------------------- ---------------------------- ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- --------------------------------------------------------------- ------------- ----------- ----------- ----------- **[HS-PS1-1]** **[HS-PS1-1]** Use the periodic table as a model to predict the relative properties of elements based on the patterns of electrons in the outermost energy level of atoms. [2,3,8,12,14,15,16,17,18,23,24,25,36,37,38,40,42] **[HS-PS1-2]** **[HS-PS1-2]** **Construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.** [4,5,6.9,10,13,22,28,35,39,41,47,49] **[HS-PS1-3]** **[HS-PS1-3]** ** compare the structure of substances at the bulk scale to infer the strength of electrical forces between particles.** [1,7,19,20,21,26,27,30,31,45,46] **[HS-PS1-7]** **[HS-PS1-7]** **Use mathematical representations to support the claim that atoms, and therefore mass, are conserved during a chemical reaction.** [11,29,32,33,34,43,44,48] **Total** [ ] [Comments] **F.A -- Above level P.A-- At Level N.A -- Below level** +-----------------+-----------------+-----------------+-----------------+ | **Proficiency | **4.0 Scale** | **Letter | **Criteria** | | Scale** | | Grade** | | +=================+=================+=================+=================+ | **Exemplary** | **4** | **A** | The student | | | | | consistently | | | | **90-100%** | and | | | | | independently | | | | | demonstrates | | | | | proficient and | | | | | advanced | | | | | understandings | | | | | of the course | | | | | concepts and | | | | | skills in a | | | | | variety of | | | | | assessments. | | | | | The knowledge | | | | | is transferable | | | | | into different | | | | | contexts. | +-----------------+-----------------+-----------------+-----------------+ | **Proficient** | **3** | **B** | The student | | | | | independently | | | | **80-89%** | demonstrates | | | | | proficiency in | | | | | the majority of | | | | | the | | | | | expectations | | | | | for his/her | | | | | grade. The | | | | | student, with | | | | | few errors, | | | | | grasps and | | | | | applies key | | | | | concepts, | | | | | processes, and | | | | | essential | | | | | skills for | | | | | his/her grade | | | | | level. | +-----------------+-----------------+-----------------+-----------------+ | **Progressing** | **2** | **C** | The student is | | | | | beginning to | | | | **70-79%** | meet | | | | | expectations | | | | | for his/her | | | | | grade with | | | | | teacher and | | | | | peer support. | | | | | The student is | | | | | beginning to | | | | | grasp key | | | | | concepts, | | | | | processes, and | | | | | essential | | | | | skills for | | | | | his/her grade | | | | | level. | +-----------------+-----------------+-----------------+-----------------+ | **Beginning** | **1** | **D** | The student is | | | | | not meeting | | | | **60-69%** | expectations | | | | | for his/her | | | | | grade. The | | | | | student is not | | | | | yet grasping | | | | | the key | | | | | concepts, | | | | | processes, and | | | | | essential | | | | | skills for | | | | | his/her grade | | | | | level. | +-----------------+-----------------+-----------------+-----------------+ | **Yet to meet** | **0** | **E** | No evidence on | | | | | which to grade | | | | **0-60%** | | +-----------------+-----------------+-----------------+-----------------+ ***[SECTION 1: Q1 35 Multiple Choice Questions (35 points)]*** ***[Directions: Each of the questions or incomplete statements below is followed by four suggested answers or completions. Select the one that is best in each case and then fill in the corresponding circle on the answer sheet]*** 1. Which statement describes the particles in a gas? Circle the letter of the correct answer. a. Gas particles are spaced far apart and move around freely. b. Gas particles are spaced far apart and move around slowly. c. Gas particles are tightly packed together and move past each other freely. d. Gas particles are loosely packed together and move past each other freely. 2. Which type of substance is always made up of two or more different types of atoms joined by chemical bonds? Circle the letter of the correct answer. a. mixture b. element c. compound d. pure substance 3. Glucose, C6H12O6, is a kind of sugar molecule. How many atoms are in a molecule of glucose? Circle the letter of the correct answer. a. 6 b. 12 c. 18 d. 24 4. When testing a pure substance for its properties, some of the tests result in the sample being changed into another substance. Testing for which of these properties may result in the sample substance being changed into a different substance? Circle the letter of the correct answer. a. density b. solubility c. boiling point d. flammability 5. Jackie has drawn a model of methane but needs help labeling it. The chemical formula for methane is CH4. Write one letter in each box to correctly label the names of the elements according to the 6. Rayon is a human-made fabric created from wood chips. Which statement describes the changes that take place when wood is made into rayon? Circle the letter of the correct answer. A. Rayon and wood have different properties because a chemical reaction rearranges the atoms into a different material. B. Rayon and wood have similar properties because a chemical reaction rearranges the atoms but does not change the material. C. Rayon and wood have similar properties because a chemical reaction softens the wood chips but does not change the material. D. Rayon and wood have different properties because a chemical reaction loosens the bonds between the atoms in the wood chips, making it into a different material. 7. The model shows in detail the structure of sodium chloride. -- -- -- -- -- -- 8. Which of these is the smallest particle to retain the properties of an element? Circle the letter of the correct answer. a. an atom b. a proton c. a molecule d. an electron 9. What makes physical properties different from chemical properties? Circle the letter of the correct answer. a. Physical properties relate to elements rather than compounds. b. Physical properties appear only after a chemical change occurs. c. Physical properties describe elements in the solid state rather than in the liquid or gas state. d. Physical properties can be observed without attempting to change the identity of the substance. 10. Bill has iron flakes, salt, and water. He puts some of the iron and salt together in a cup and mixes them together. He makes a table to describe all the different substances he has. Write an X in the boxes in the table that correctly describe each substance. Some substances may have more than one X. 11. Chemical equations are models that show how atoms are rearranged during a chemical reaction. Liza wrote an equation for the reaction between aluminum (Al) and copper sulfate (CuSO4) that is shown. 12. Which statement describes a mixture of salt and water? a. Homogeneous mixture: the components are uniformly mixed. b. Heterogeneous mixture: the components are uniformly mixed. c. Homogeneous mixture: the components are not uniformly mixed. d. Heterogeneous mixture: the components are not uniformly mixed. 13. A student makes several observations about a solid metal. Which statement explains why the observation described is a physical change? a. *The metal turns black when exposed to air* is a physical change because the color of the metal changed. b. *The metal forms a red solid when placed in solution* is a physical change because there was no change of state. c. *The bubbles form when the metal is added to an acid* is a physical change because a change of state from solid to gas occurred. d. *The metal becomes a liquid when heat is applied* is a physical change because the metal's chemical properties remained the same. 14. In the gold foil experiment, positive particles were directed at gold atoms to find out about the interior of an atom. Which direction recorded the most particles to support the claim that an atom is mostly empty space? a. Direction A b. Direction B c. Direction C d. Direction D 15. The figure shows elements in the same period and group of the periodic table where germanium is located. Which element(s) have a ***lower ionization energy*** than germanium (Ge)? Circle all the correct answers. 16. **Which of the following is the correct electron configuration of Sulfur?** a. **1s2 2s2 2p6 3s2 3p3** b. **1s2 2s2 2p6 3s2 3p4** c. **1s2 2s2 2p6 3s2 3p5** d. **1s2 2s2 2p6 3s2 3p6** 17. **Isotopes are.** a. **Elements with same atomic number and same mass number** b. **Elements with same atomic number and different mass number** c. **Elements with different atomic number and same mass number** d. **Elements with different atomic number and different mass number** 18. A mystery element has 18 protons. Which one of the following statements is **true** about the element? a. The element belongs in row 2 of the periodic table and is classified as a halogen. b. The element belongs in row 3 of the periodic table and is classified as a noble gas. c. The element belongs in row 4 of the periodic table and is classified as an alkali metal. d. The element belongs in row 5 of the periodic table and is classified as an alkaline earth metal. 19. The list identifies various properties of four elements: Element 1 is a gas at room temperature. Element 2 is a solid which conducts electricity. Element 3 is a gas with forms a negative ion of -1. Element 4 is malleable and can take the form of a shiny solid sheet. Based on this list, which elements are metals? a. Elements 1 and 3 b. Elements 1 and 4 c. Elements 2 and 3 d. Elements 2 and 4 20. Which pair of words correctly completes the statement? Alkali metals are highly \_\_\_ since they \_\_\_ easily to form ions. a. nonreactive; lose 1 electron b. nonreactive; lose 2 electrons c. reactive; lose 1 electron d. reactive; gain 1 electron 21. The diagram shows the electron configuration around the chlorine nucleus. Chlorine has 17 protons.  Which of the following correctly completes the statement? Chlorine has \_\_\_\_ valence electrons, and the Atomic number, for the chlorine atom shown is \_\_\_\_\_\_. a. 7; 7 b. 7; 17 c. 10; 7 d. 7; 35 22. Which list arranges the elements Na, Li, K, Rb, and Cs in order of increasing ionization energy (from left to right)? a. Cs; Rb; K; Na; Li b. Cs; Li; Na; K; Rb c. Na; Li; K; Rb; Cs d. Li; Na; K; Rb; Cs 23. With the exception of He, how many valence electrons do noble gases have? a. 3 b. 4 c. 6 d. 8 24. Which characteristic is **not** a periodic trend? a. atomic radius b. electron affinity c. ionization energies d. number of elements in a group 25. Select the answer that shows the words in the correct order to complete the sentence. a. protons; core b. electrons; valence c. neutrons; inner d. electrons; middle 26. Which of the following Lewis structures correctly represent CaCl~2~? a. Option 1: Lewis diagram of a C l ion with 8 valence electrons and negative charge , a C a ion with no electrons and a positive 2 charge, and a C l ion with 6 valence electrons and negative charge. b.  c. Lewis diagram of 2 C l ions with 8 valence electrons and negative charge and C a with no electrons. d.  27. Which of the following statements about metals are **true**? Select all that apply. a. Metals can be drawn into wires. b. Metals have low melting and boiling points. c. Metals can be hammered into different shapes. d. Metals in solid form have specific crystal structures. e. Metals are not able to conduct electricity due to stationary electrons. f. The sea of electrons holds metal anions together throughout the entire solid. 28. Which of the following statements about covalent bonds are **true**? Select all that apply. a. Covalent bonds are comprised of metal atoms that share at least some of their valence electrons. b. Covalent bonds hold the atoms together in discrete molecules. c. Covalent bonds form when atoms of nonmetals are close enough to each other for their orbitals to overlap. d. Covalent bonds can be single, double, or triple bonds. e. Covalent bonds hold ionic compounds together. 29. The number of MOLES represented by 8.67 x 10^18^ atoms of Zn is: a\. 1.44 b\. 1.44 x 10^-5^ c\. 4.5 x 10^-20^ d^.^ 8.6 x 10^-4^ 30. The diagram models metallic bonding. What about the electrons in metal elements contributes to metallic bonding? a. All electrons move within pairs of atoms. b. All electrons are attracted to several nuclei. c. Outer electrons are able to move freely within the sample. d. Outer electrons are tightly held by the nucleus in each atom. 31. What would be the general formula unit of a compound made with a Group 1 element, A, and a Group 16 element, Z, from the periodic table? Refer to the periodic table. a. AZ b. AZ~2~ c. AZ~16~ d. A~2~Z 32. Which statement explains how balanced chemical equations obey the law of conservation of mass? a. The products and reactants are the same chemicals. b. The subscripts of the reactants equal the subscripts of the products. c. The coefficients of the reactants equal the coefficients of the products. d. The same number of each kind of atom appears in the reactants and in the products. 33. Oxygen can combine with carbon to form carbon dioxide (CO~2~) according to the equation below. a. law of conservation of energy b. law of conservation of mass c. law of multiple proportions d. law of definite proportions 34. Which coefficients correctly balance the equation? NH~4~NO~2~(*s*) N~2~(*g*) + H~2~O(*l*) a. 1, 1, 2 b. 1, 2, 2 c. 2, 1, 1 d. 2, 2, 2 35. In what kind of reaction do two or more substances combine to form a new compound? a. synthesis reaction b. combustion reaction c. decomposition reaction d. double-displacement reaction **SECTION 2 :Q 114-: FREE RESPONSE QUESTIONS (25 points)** **Directions:** **Read Questions thoroughly Write full answers on lines provided.** **For** **parts** **of** **the** **free-response** **question** **that** **require** **calculations,** **clearly** **show** **the** **method** **used** **and** **the** **steps** **involved** **in** **arriving** **at** **your** **answers.** **You** **must** **show** **your** **work** **to** **receive** **credit** **for** **your** **answer.** **Examples** **and** **equations** **may** **be** **included** **in** **your** **answers** **where** **appropriate** 36. Matter can be classified in many different ways. (1 pts ) Classify glucose and air by describing the type of substance each is, such as element, compound, mixture, or type of mixture. [\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_] 37. Write the letter of the group name from each numbered list to correctly label the parts of the periodic table. ( 2 pts ) **1.** \_\_\_\_\_\_\_\_ **2.**\_\_\_\_\_\_\_\_  **3.** \_\_\_\_\_\_\_\_ **4.** \_\_\_\_\_\_\_\_ **5.** \_\_\_\_\_\_\_\_ -- -- -- -- -- -- -- -- -- -- 38. Fill in the boxes to correctly describe the valence shells of the atoms of the elements in different groups of the periodic table. (2 pts) -------------------------------- Periodic table of the elements -------------------------------- Ca O Ar --------------------------------------- ---- --- ---- Outer shell status (full or not full) Valence electrons Ions formed 39. Provided a graph of first ionization energies for the first 20 elements. Interpret graph data to explain trends in ionization energy (2 points) 40. In the space below, write the complete electron configurations of (2pts) a. Nickel b. krypton 41. The periodic table shows trends in properties of the elements. (3 points) a. Describe the trends in electronegativity, atomic radius, and reactivity in the periodic table. [\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_] b. Explain the relationship between an element's electronegativity and its atomic radius. [\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_] 42.. Chlorine has two isotopes. Chlorine-35 has an actual mass of 34.9689 u and chlorine-37 has a mass of 36.9659 u. In any sample of chlorine atoms, 75.771% will be chlorine-35 and 24.229% will be chlorine 37. Calculate the average atomic mass of chlorine. (2 points) [\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_] [\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_] 43. Calculate the molar mass (g/mol) of each of the following (show work for at least the first 2) ( 3points) a. MgSO~4~ b. H~2~O~2~ 44. Calculate the number of representative particles (show work for at least the first 2) (2 points) 45. A student writes Ba^2--^ as the symbol for a barium ion. Explain what is incorrect about the symbol. (1 points) 46. Locate lithium, bromine, and oxygen on the periodic table. (2points) a. Identify the two pairs of elements that will combine to form ionic compounds. Name each compound and its chemical formula. b. Explain why these combinations of elements form ionic bonds, using knowledge of trends and patterns in the periodic table. 47. Describe two observations that indicate that a chemical reaction has occurred. (1 point) 48. In a combustion reaction, butane (C~4~H~10~) burns in oxygen (O~2~) to produce carbon dioxide (CO~2~) and water. Write and balance the chemical equation for the combustion of butane. (1 point) 49. Silver, Ca(*s*), is combined with potassium nitrate, MgCl~2~(*aq*). (2 points)