Topic 1 & 2
The two main types of changes are
What is Physical and Chemical changes?
The product diagram for the equation 2NO(g) + O2(g) --> 2NO2 (g) would look like _______ with eight NO(g) and two O2 (g)?
What is four NO2(g) and four excess NO(g)?
( OPTIONAL: and zero O2(g) ? )
Titrations are...
What is laboratory experiments where we use a buret to slowly add a solution to a flask of a different solution?
LEO-GER is
What is Losing electrons oxidation, gaining electrons reductions?
Half-reactions help us (hint: think electrons)
What is help see where electrons are going?
The balance to this equation:
PCl5 + H2O --> H3PO4 + HCl
What is (1)PCl5 + (4)H2O --> (1)H3PO4 + (5)HCl ?
The dissolving of an ionic compound is a _____ change, but it has _____ aspects to it, as well.
What is Physical and Chemical?
To decide a limiting reactant you...
What is do the problem twice and see which reactant produces less product?
In precipitation reactions (hint: what combine and form solid)
What is two soluble ionic compounds combine, and the two of the ions join together to form a solid precipitate?
Oxidation and reduction in this reaction is
Zn (s) --> Zn2+(aq) + 2e-
3e- + Au3+(aq) --> Au (s)
What is (for Zn) oxidation and (for Au) reduction?
Physical changes are
What is change in appearance or state?
In the case of sodium chloride (dissolving), the negative poles of water surround the _____ _____, and the positive poles of water surround the ______ ______.
What is Sodium cations (or Na+) ; Chloride anions (or Cl-)?
What steps would be taken for the problem:
If a chemist desires to produce 1.00g of NO2 gas, what mass of copper metal should be dropped into excess nitric acid? Cu(s) + 4HNO3(aq) --> 2H2O (L) + 2NO2(g) + Cu(NO3)2 (aq)
What is convert to moles of NO2 to 1Cu, then mole ratio, then convert to final unit (g Cu)?
Acid-Base reactions (involve the transfer of H+ ion) in terms of redox... (3 things to include)
What is involve the transfer of electrons, losing electrons in oxidation and gaining in reduction, every atom in every compound or ion has an oxidation state?
In the reaction Cl2 + 2Br- → 2Cl- + Br2, this species is the reducing agent and this is the total number of electrons transferred.
What is Br-; 2 electrons?
Name three signs of chemical change
What is light, gas produced, heat change, change of color, and/or precipitate
When solid iodine is heated, it forms a purple vapor that can later return to solid crystals on a cool surface without any change in composition.
What is a physical change?
The exact moment where the moles of base that we’ve added from the buret is equal to the moles of acid present in the flask is called
What is equivalence point?
At the equivalence point of a titration between a strong acid and a strong base, the pH of the solution has this value at 25°C.
What is 7 pH?
The oxidation number of sulfur in SO4(2-) is this value.
What is +6?
All ___ and ___ are soluble.
What is all nitrates and alkali metal ions?
In an ionic compound like chloride... (think of lattice breaking)
What is ionic bonds have to be broken when this crystal lattice is broken apart?
When 30.0 mL of 0.150 M AgNO3 reacts with excess NaCl, this many moles of AgCl(s) precipitate.
What is 0.00450 moles?
During the titration of a weak acid with a strong base, the pH of the solution is measured to be 4.75 when exactly half of the acid has been neutralized. This is the value of the acid’s pKa.
What is 4.75 pH?
In acidic solution, the following unbalanced redox reaction occurs:
MnO4(-) + Fe2+ --> Mn2+ + Fe3+
This is the number of electrons transferred when the equation is fully balanced.
What is 5 electrons?