Le Chatelier’s Principle/Ocean Acidification/Antacid Neutralization Rxns
The following reaction is exothermic:
N2(g)+3H2(g)⇌2NH3(g)+heatN2(g)+3H2(g)⇌2NH3(g)+heat
If the temperature is increased, in which direction will the equilibrium shift? Explain your reasoning.
The equilibrium will shift to the left (toward the reactants). Increasing temperature adds heat, which acts as a product in an exothermic reaction. According to Le Chatelier’s Principle, the system will shift to use up the added heat, favoring the endothermic (reverse) direction
Question:
What is the pH of a 0.0025 M HCl solution?
HCl is a strong acid and dissociates completely, so [H+] = 0.0025 M.
Given the reaction:
2 Al+3 Cl2→2 AlCl32Al+3Cl2→2AlCl3
If you have 5.0 grams of aluminum and 6.0 grams of chlorine gas, which reactant is limiting, and how many grams of AlCl3AlCl3 can be produced?
Cl₂ is limiting; 7.57 g of AlCl₃ can be produced
What is the molar mass of aluminum sulfate, Al2(SO4)3Al2(SO4)3?
53.96+96.21+192.00=342.17g/mol
What is the correct name for the compound with the formula K2O?
K2O is composed of potassium (K) and oxygen (O).
According to nomenclature rules for binary ionic compounds, the metal (potassium) is named first, and the nonmetal (oxygen) is named second with its ending changed to –ide.
Name: Potassium oxide
Consider the equilibrium:
Fe3+(aq)+SCN−(aq)⇌FeSCN2+(aq)Fe3+(aq)+SCN−(aq)⇌FeSCN2+(aq)
What will happen to the concentration of FeSCN2+ if more Fe3+ is added to the system at equilibrium? Why?
The concentration of FeSCN2+ will increase. Adding Fe3+ increases the concentration of a reactant, so the equilibrium shifts to the right to produce more product and use up the added reactant
Label the following equation with BLA (Bronsted-Lowry Acid), BLB (Bronsted-Lowry Base), CA (Conjugate Acid), CB (Conjugate Base), and mark the acid-conjugate base and base-conjugate acid pairs:NH3(aq)+H2O(l)⇌NH4+(aq)+OH−(aq)
NH3: BLB (Bronsted-Lowry Base)
H2O: BLA (Bronsted-Lowry Acid)
NH4+: CA (Conjugate Acid)
OH− : CB (Conjugate Base)
How many grams of water are produced when 18.0 grams of glucose (C6H12O6C6H12O6) are completely combusted?
C6H12O6+6 O2→6 CO2+6 H2OC6H12O6+6O2→6CO2+6H2O
10.8 g of water are produced.
Write the balanced molecular equation and predict the products for the reaction between aqueous solutions of sodium sulfate (Na2 SO4 Na2 SO4) and barium chloride (BaCl2 BaCl2).
Na2SO4(aq)+BaCl2(aq)→2NaCl(aq)+BaSO4(s)
Write the chemical formula for calcium nitrate.
Calcium is Ca2+; nitrate is NO3−
To balance the charges, two nitrate ions are needed for each calcium ion.
Formula: Ca(NO3)2
Explain how increasing atmospheric CO2, CO2 levels can lead to a decrease in the availability of carbonate ions (CO3 2−CO3 2−) in ocean water. Why is this a problem for marine organisms?
More atmospheric CO2 dissolves in seawater, forming carbonic acid, which dissociates and increases H+ concentration. The extra H+ reacts with carbonate ions to form more bicarbonate, decreasing the amount of available carbonate.
What is the pOH of a solution with [OH−]=0.155 M[OH−]=0.155M?
the pOH is 0.81
What is the molarity of a solution made by dissolving 4.00 grams of NaOH in enough water to make 250.0 mL of solution?
0.400 M
Will zinc metal react with copper(II) sulfate solution? If so, write the balanced equation.
Zinc is above copper in the activity series, so the reaction occurs.
Zn(s)+CuSO4(aq)→ZnSO4(aq)+Cu(s)Zn(s)+CuSO4(aq)→ZnSO4(aq)+Cu(s)
What is the correct name for the compound Mg(NO3)2Mg(NO3)2?
The cation is magnesium (Mg2+).
The anion is nitrate (NO3−), a polyatomic ion.
The compound is named by stating the cation first, followed by the name of the polyatomic ion.
Name: Magnesium nitrate
Write a balanced chemical equation for the reaction between calcium carbonate (CaCO3CaCO3), a common antacid, and hydrochloric acid (HClHCl) in the stomach. What products are formed?
CaCO3(s)+2HCl(aq)→CaCl2(aq)+CO2(g)+H2O(l)
Explain how increased atmospheric CO₂ contributes to ocean acidification and affects marine life.
Increased atmospheric CO₂ dissolves in ocean water, forming carbonic acid, which releases H+H+ ions and lowers pH. This increased acidity reduces carbonate ion availability, making it harder for marine organisms like corals and shellfish to build shells and skeletons, threatening marine ecosystems.
For the reaction:
4 NH3+5 O2→4 NO+6 H2O4 NH3+5O2→4NO+6H2O
What is the mole ratio of NH₃ to H₂O, and how many moles of water are produced from 2.0 moles of NH₃?
Mole ratio NH₃:H₂O is 4:6, which simplifies to 2:3.
For 2.0 mol NH₃: 2.0 mol×64=3.0 mol H2O2.0mol×46=3.0molH2O
Classify each reaction as synthesis, decomposition, single displacement, double displacement, or combustion:
a) 2H2 O2→2H2O+O2 2H2O2→2H2O+O2
b) 2C2H6+7O2→4CO2+6H2 O2C2H6+7O2→4CO2+6H2O
a) Decomposition (one compound breaks into two or more substances)
b) Combustion (hydrocarbon reacts with oxygen to produce carbon dioxide and water)
Write the chemical formula for ammonium fluoride.
Formula: NH4F
Consider the equilibrium reaction:
A+2B⇌C+DA+2B⇌C+D
If product C is continuously removed from the system as it forms, what will happen to the position of equilibrium? Explain your reasoning.
The equilibrium will shift to the right, toward the products. According to Le Chatelier’s Principle, removing a product decreases its concentration, so the system responds by producing more C (and D) to counteract this change, favoring the forward reaction
If a solution has a pH of 4.7, what is its pOH? (Assume 25°C)
At 25°C: pH+pOH=14pH+pOH=14pOH=14−pH=14−4.7=9.3pOH=14−pH=14−4.7=9.3
pOH = 9.3
Given the reaction:
2Mg+O2→2MgO\ce2Mg+O2→2MgO
If you have 2.40 g of Mg and 10.0 g of O₂, which reactant is limiting, and how many grams of MgO can be produced?
Mg is limiting; 3.98 g of MgO can be produced
Balance the following equation:
C3H8+O2→CO2+H2O C3H8+O2→CO2+H2O
C3H8+5O2→3CO2+4H2O
3 C on both sides, 8 H on both sides, 10 O on both sides.
What is the correct name for the compound KClO3?
Name: Potassium chlorate