Chemistry

Circle the correct answer (#1 to 10). 

1) Which of the following ions are iso-electric with (Ar)?
a) Fe and Br               b) Rb⁺and Br^–            c) Sc          d) Cl^–

• The atom must likely to gain neon electron configuration by losing one or more electrons?

1. S b) Ba               c) F            d) Mg

• What is the symbol for the following elementor ion: 17 protons, 18electrons?

1. Ne⁰ b) Al⁺³                c) Mg⁺²         d) Cl^-1

• How many electrons are in the following ion? Pb⁺²

207. 82 b) 207.7           c)80               d) 78

• Which of the following equals half the atomic mass of Oxygen atom?

1. 8 neutrons b) 16 electrons c) 18 positrons d) 6 neutrons

• Which of the following is more electronegative?

1. Ag B) P       c) Sr             D) N

• The atom with the most valence electrons is

1. P b) Al               c) B          d) C

• When an electron and positron collide their minute masses are completely converted
  a) None is correct b) new atom    c)  Gamma rays      D) protons
• Which is a Polyatomic ion?

1. O^-2 b) PO₄^-3      c) NaOH           d) CN^–

• Ca⁺² +  PO₄^-3      ————>

1. Ca²PO4^-3 b)  Ca₃PO4             c) Ca₂(PO4)₃        d)Ca₃(PO4)₂

True or False (#11 to 18)

11) H₂O and HCl both have Covalent bonds ___________
12) Covalent bonds are stronger than Ionic bonds ________
II) Bromine’s (Br) atomic radius is smaller than that of Iodine (I) ________
13) The shape of a molecule depends on electrons around itsinner atom____________
14) The arrangement of the electrons around the central atom of an Ammonia (NH₃) molecule causes it to have a Linear shape___________
15) Methane (CH₄) is an example of a nonpolar molecule___________
16) There are many ionic bonds in water____________
17) Franciumis more reactive than Barium________________
            18) When an unstable nucleus emits Gamma particles, gloves and a lab coat are enough to protect a doctor from harmful radiation___________

Answer the questions completely

19) Using the periodic table arrange the following atoms in order of increasing electronegativity?

1. a) SC, SI, V, Fe —> ___ ___  ____   ____
   b) P, Si, Al, Mg—> ___  ____  ___ ___ ____
   c) I, P, Br, At —-> ____  ____  ___
   d) Ra,Sr, Mg, Be, Ca—> ____  ____  ____  _____  _____

20) Indicate the positive(+) and negative(-) end for each of the following using signs – +, l—->?
You can use a periodic table

1. a) Na—O b) Si—–P             c)N—-Cl           d) N—-C

21) write the electron dot structure for the following
a) P
b) N
c)Si
d) Ba
e) Cl^–

22) Name the following compounds
a) PBr₃________

1. b) CF₂_________
2. c) CCl_{3 ________________}
   
   d) KHSO_{3 ___________________}

   23) Givetwo uses of medical application of radioactivity

24) What is a radioactive atom? Give two examples

25) Write the symbol the following?

1. a) Beta Particle
   b)Alpha Particle
   c)Gamma Particle
   d) Positron

26) Complete the nuclear equations(?) for the following

207. a) ²₈₂Pb——————————–>? + ⁰_-1e

     b) ^50.94₂₃V—————————->?     +   ⁰₀γ

     c)^95.94₄₂Mo ——————————>?      +  ⁰₊₁e

     d) ?——————————–>²³⁷₉₃Np +     ⁴₂He + 4¹₁H

27) Suppose a piece of wood found in a tomb (has 2 half-lives) of its original carbon-14 (one half-liveis 5730 yrs)activity. About how many years was the wood tree alive?

29) Define the following terms
a) Oxidation
b) Nuclear fusion
c)Nuclear fission
d)Covalent bond
e) Half-life

29) Complete the following cation-anion reactions

1. a) Be⁺³ + (NO₃)^-2   —————–>
   b) Cu⁺¹  +  SO₄^-2—————->
   c) Ca⁺²   + Cr₂O₇^-2  —————->
   d) Pb⁺⁴  +  PO₃^-3 ————>

Use Salt Solubility Tables

30) Assuming that each single-replacement reaction occurs, predict the products and write each balanced chemical equation

1. Mg + HCl → ?
2. HI + Br₂ → ?

(B) Use the periodic table or the activity series to predict if each single-replacement reaction will occur and, if so, write a balanced chemical equation

1. FeCl₂ + Br₂→ ?
2. Fe(NO₃)₃ + Al → ?

(C)  Use the periodic table or the activity series to predict if each single-replacement reaction will occur and, if so, write a balanced chemical equation

1. Zn + Fe₃(PO₄)₂→ ?
2. Ag + HNO₃ → ?

(D) Use the periodic table or the activity series to predict if each single-replacement reaction will occur and, if so, write a balanced chemical equation

1. NaI + Cl₂→ ?

b.AgCl + Au → ?