Aqueous hydrochloric acid reacts with solid sodium hydroxide to produce aqueous sodium chloride and liquid water what is the terorectical yield of water formed from the reaction of 3.3 g of hydrocloric acid and 6.6g of sodium hydroxide?

1.63 g of H₂O is the theoretical yield

Explanation:

We determine the reactants for the reaction:

HCl, NaOH

We determine the products for the reaction:

H₂O, NaCl

The equation for this neutralization reaction is:

HCl (aq) + NaOH(aq) → NaCl(aq) + H₂O(l)

We use both masses, from both reactants to determine the limiting.

First, we convert the mass to moles.

3.3 g . 1mol / 36.45 g = 0.090 moles of HCl

6.6 g . 1mol / 40 g = 0.165 moles of NaOH

Ratio is 1:1, so for 0.165 moles of hydroxide I need the same amount of acid. I have 0.090 HCl so the acid is the limiting reagent.

Let's work with stoichiometry. Ratio is 1:1, again.

1 mol of acid can produce 1 mol of water

Therefore, 0.090 moles of acid must produce 0.090 moles of H₂O

We convert the moles to mass, to define the theoretical yield

0.090 mol . 18g / 1 mol = 1.63 g

The theoretical yield of H2O is 1.63 grams

Explanation:

Step 1: Data given

Mass of hydrochloric acid = 3.3 grams

Mass of sodium hydroxide = 6.6 grams

Molar mass hydrochloric acid (HCl) = 36.46 g/mol

Molar mass sodium hydroxide (NaOH) = 40.0 g/mol

Step 2: The balanced equation

HCl + NaOH → NaCl + H2O

Step 3: Calculate moles

Moles = mass / molar mass

Moles HCl = 3.3 grams / 36.46 g/mol

Moles HCl = 0.0905 moles

Moles NaOH = 6.6 grams / 40.0 g/mol

Moles NaOH = 0.165 moles

Step 4: Calculate the limiting reactant

HCl is the limiting reactant. There will react 0.0905 moles. NaOH is in excess. There will react 0.0905 moles moles. There will remain 0.165 - 0.0905 = 0.0745 moles

Step 5: Calculate moles H2O

For 1 mol HCl we need 1 mol NaOH to produce 1 mol NaCl and 1 mol H2O

For 0.0905 moles HCl we'll have 0.0905 moles H2O

Step 6: Calculate mass H2O

Mass H2O = moles * molar mass

Mass H2O = 0.0905 * 18.02 g/mol

Mass H2O = 1.63 grams

The theoretical yield of H2O is 1.63 grams

1. the question asks the most appropriate, which seems to rule out "all of the above." your choice appears to be the correct one.

2. the protocol described is good for identifying correlation, but not cause and effect. for cause/effect, you need to devise a protocol that will assign the treatment (or not) to groups that have essentially the same "demographics" with respect to all the other variables. your choice regarding control group seems appropriate. random assignment of treatment (choice d) may be appropriate also. (i think you can argue that b and d are just different descriptions of the same method.)

3. d will randomize the birds, but may not guarantee there are 10 in each group. e will do both, so seems the better choice.

comment on question 2

based on the problem statement, it seems clear that confident, attentive drivers are more likely to use daytime running lights. so, the protocol might need to be devised in such a way that the lights would be turned on or off without the driver's knowledge. (an attentive driver will figure it out.) assigning a confident, attentive driver to a group required to drive without running lights might mess with his/her confidence and attentiveness. you don't want your experiment to do that. (nor do you want the experiment to subject a driver to greater risk of accident as a consequence of driving without running lights.) experiments involving human safety are always problematic.