The HCl added = 1.25 moles
and the moles of Na2HPO4 = 1 mole
Now when acid is added in the given solution of Na2HPO4
One mole of H+ will react with one mole of Na2HPO4 to given one mole of NaH2PO4
Na2HPO4 + H+ ---> NaH2PO4
Now this one mole formed NaH2PO4 will further react with 0.25 moles of H+ left to form 0.25 moles of H3PO4 and 0.75 moles of NaH2PO4 will remain in the solution
So this will result into formation of a buffer of phosphoric acid and NaH2PO4
NaH2PO4 + H+ ---> H3PO4
pKa of H3PO4 = 2.1
so pH = pKa + log [salt] / [acid] = 2.1 + log [0.75 / 0.25] = 2.58
so the pH will be in between 2.1 to 7.2
A source of error is any factor that may affect the outcome of an experiment. There are countless conceivable sources of error in any experiment; you want to focus on the factors that matter most. Identify each source of error specifically and then explain how that source of error would have affected the results. Keep in mind that an "error" to a scientist does not mean "mistake"; it more closely means "uncertainty".
Many students are tempted to say "human error", but this term is vague and lazy; any decent teacher will not accept it. Instead, think about specific things that happened during the lab exercise where the end results may have been affected.
To give an example one might find in a bio lab: perhaps a water bath's temperature was not monitored very carefully and you found that an enzyme's activity was greater than you expected. In that case, you could write something like,
"The temperature of the water bath during this exercise was not monitored carefully. It is possible that it was warmer or cooler than intended, and this would have affected the enzyme activity accordingly. The fact that our enzyme activity was found to be higher than expected leads me to believe that perhaps the water bath was too warm."
Answer:
The answer is combustion.
Answer:
<h2>59.1 m</h2>
Explanation:
The height of the object can be found by using the formula

where
p is the potential energy
m is the mass
h is the height
g is the acceleration due to gravity which is 10 m/s²
From the question we have

We have the final answer as
<h3>59.1 m</h3>
Hope this helps you
Moles of X are 0.925 moles.
A mole is a totally vital unit of dimension that chemists use.The mole, symbol mol, is the unit of amount of substance inside the worldwide device of gadgets. the amount quantity of the substance is a measure of how many simple entities of a given substance are in an item or sample. The mole is described as containing exactly 6.02214076×10²³ primary entities
mass of X2O3 = 4 g
so moles = mass/molar mass
molar mass of X2O3 = 2*X + 48 -
Given, that the mass of X = 2.8g
mass of O = 4 - 2.8 = 1.2g
A mole of O = 1.2g/16 = 0.075 mole
∴ mole of X = 1 - 0.075 = 0.925 moles.
Learn more about moles here:-brainly.com/question/15356425
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