شرح للكيمياء و أسئلة مراجعة

[سحر البيان]

11- Which of the following is NOT a molecular compound?

a) CO2 b) H2O c) S8 d) C3H8

12- Which of the following is an ionic compound?
a) chlorine, Cl2 b) carbon dioxide, CO2
c) Sodium carbonate Na2CO3 واضح
d) C3H8


13- Which of the following names and formulas are NOT paired correctly?
a) sodium chloride, NaCl
b) lead(II) nitrite, Pb(NO2)2
c) ammonium sulfate, (NH4)2SO4
d) copper(II) sulfate , CoSO4
اللي موجود رمز الكزبلت و ليس النحاس


14-Which of the following names and formulas are NOT paired correctly?
a) nitrogen oxide, NO

لأنه ما كتبوا مونو أظن قبل شوي حليت زيه بس بصيغة مختلفة

b) nitrogen triiodide, NI3
c) dichlorine monoxide, Cl2O c) disulfur pentafluoride, S2F5


13- What is the formula mass of calcium nitrate, Ca(NO3)2?
a) 102.1 b) 164.1 c) 204.2 d) 150.1 سهل

12- Ammonium nitrate (NH4NO3), a common fertilizer, is 35.0% nitrogen by mass. How much ammonium nitrate contains 1.25 kg of nitrogen?
a) 3.57 kg b) 437 g c) 15.61 kg d) 230 kg



13- A nitrogen oxide is 63.65% by mass nitrogen. The molecular formula could be:
a) NO b) NO2 c) N2O d) N2O4

14- The following data were collected when analyzing a compound used in dentistry to cement repaired teeth: 50.82% Zn; 16.04% P; 33.14% O what is the empirical formula of the compound?
a) Zn3PO2 b) Zn16P5O10 c) Zn3P2O8 d) Zn6P2O4

15- When the following equation is balanced, what is the coefficient in front of H2O?
___ Ba(OH)2 + ___ H3PO4 → ___ H2O + ___ Ba3(PO4)2

a) 3 b) 2 c) 6 d) 4


16- The mineral manganosite is a compound of manganese and oxygen. If 77% of the mass of manganosite is due to manganese, what is the empirical formula of manganosite?
a) MnO b)Mn2O c)Mn2O2 d)MnO2 e)none of these

17- The formula for sodium sulfide is
a) NaS. b) K2S. c) NaS2 d) Na2S


18- Which is the correct formula for copper(II) phosphate?
a) Cu2PO4 b) Cu3(PO4)2 c) Cu2PO3 d) Cu(PO4)2

19- What is the formula for the ionic compound formed by calcium ions and nitrate ions?
a) Ca3N2 b) Ca(NO3)2 c) Ca2NO3 d) CaNO3

20- A magnesium ion, Mg2+, has …. protons and…… electrons.
a) 12, 13 b)24 ,26 c) 12, 10 d) 24 , 22
هذا السؤال عالمي لاحظتوا بيتكرر بكم صيغة

21-An oxide ion, O2-, has …. protons and…… electrons
a) 8, 10 b) 10 ,8 c) 8, 9 d) 8 , 9

22- Two isotopes of an element differ only in their
a) Symbol. b) atomic number c) atomic mass
d) number of electrons

23- An atom of the isotope sulfur-31 consists of how many protons, neutrons, and electrons? (p = proton, n = neutron, e = electron)
a) 16 p, 16 n, 15 e b) 16 p, 15 n, 16 e c) 16 p, 31 n, 16 e d) 32 p, 31 n, 32 e

24- Which one of these species is an ion?
a) B3+
b) NaCl c) He d) 14C

أيون يعني عليه شحنة

25-Atoms of the same element with different mass numbers are called
a) Ions b) neutrons. c) allotropes d) isotopes.

لو تلاحظوا هذا السؤال برضوا تكرر بكذا صيغة