Mixtures, compounds, and solutions
Which of the following are homogeneous mixtures?
I. An aqueous solution of sodium chloride
II. A mixture of pentane and hexane
III. A mixture of ethanol and water
I, II and III
Which species has the weakest conjugate base?
A. CH3COOH
B. H2SO4
C. NH3
D. H2O
B. H2SO4
What is the maximum number of electrons that can occupy a p-orbital?
2
The pH of water at room temperature.
7
What is the coefficient for HCl when the equation below is balanced?
__Na2S(s) + __HCl (aq) → __NaCl (aq) + __H2S (g)
8
Which is correct?
A. Mixtures are either homogeneous or heterogeneous and their chemical properties are an average of the individual component properties.
B. Mixtures are never heterogeneous and their chemical properties are an average of the individual component properties.
C. Mixtures are either homogeneous or heterogeneous and the components retain their individual chemical properties.
D. Mixtures are never homogeneous and the components retain their individual chemical properties.
C. Mixtures are either homogeneous or heterogeneous and the components retain their individual chemical properties.
What is the correct way to express the formula for the conjugate base of perchloric acid?
ClO4−
Which of the following would have the same numerical value for all elements in the same period?
A. Highest energy levels occupied
B. Energy sub-levels occupied
C. Orbitals occupied
D. Valence electrons
A. Highest energy levels occupied
Which 0.05 mol dm–3 aqueous solution has the highest pH?
A. HCl
B. H2SO4
C. NaOH
D. HNO3
C. NaOH
Ammonia reacts with oxygen to produce nitrogen (II) oxide and water.
___ NH3 (g) + ___ O2 (g) → ___ NO (g) + ___ H2O(l)
What is the NH3:O2 ratio in the balanced equation?
4:5
What type of mixture is steel?
Alloy
Which species are acids in the equilibrium below?
H2O(l) + NH3(aq) ⇌ OH–(aq) + NH4+(aq)
H2O and NH4+
The answer to every single question on the midterm exam.
What is "A"?
What is the pH of 0.001 mol dm−3 HCl (aq)?
3
64 g of methane and 96 g of oxygen are reacted according to the equation.
CH4 (g) + 2O2 (g) → CO2 (g) + 2H2O (l)
What would be found in the reaction vessel at completion of the reaction?
CH4 (g), CO2 (g) and H2O (l) only
Which of the following is NOT a property of a mixture?
The original properties of the combined substances are changed
Which cannot act as a Brønsted–Lowry base?
A. HPO42−
B. H2O
C. O2
D. NH4+
C. O2 and NH4+
What is the maximum number of electrons that can occupy the fourth shell in the atom (n = 4)?
32
Which of the 0.001 mol dm−3 solutions is most likely to have a pH of 11.3?
A. Ba(OH)2 (aq)
B. NaOH(aq)
C. LiOH (aq)
D. KOH (aq)
A. Ba(OH)2 (aq)
0.02 mol of zinc is added to 10.0 cm3 of 1.0 mol dm–3 hydrochloric acid.
Zn (s) + 2HCl (aq) → ZnCl2 (aq) + H2 (g)
How many moles of hydrogen are produced?
0.005
Define mixture.
When two or more substances mix without undergoing any chemical change, the resulting substance is referred to as a Mixture in chemistry.
The result of the combination of substances does not lose its uniqueness, nor are they chemically combined. A mixture is the end result of mechanically blending or mixing chemical substances such as elements and compounds.
Name the 7 strong acids talked about in class.
hydrochloric acid (HCl), nitric acid (HNO3), sulfuric acid (H2SO4), hydrobromic acid (HBr), hydroiodic acid (HI), perchloric acid (HClO4), and chloric acid (HClO3)
State the electron configuration of copper.
1s2 2s2 2p6 3s2 3p6 4s1 3d10
OR
[Ar] 4s1 3d10
The following equation represents the dissociation of water at 25 °C.
2H2O (l) ⇌ H3O+ (aq) + OH− (aq) ΔH = -56 kJ
Which changes occur as the temperature decreases?
[H3O+] increases and pH will decrease.
What volume of carbon dioxide, CO2 (g), can be obtained by reacting 1 dm3 of methane, CH4 (g), with 1 dm3 of oxygen, O2 (g)?
0.5 dm3