The strong Base with a pH of 12 is reduced by 4 units upon being added with solution Y. If you added a strong acid to the strong base, all ions are present in the solution, yes? So every OH- is neutralised by every H+ for example, meaning the resultant pH should be 7. The resultant pH is only 8 however, so solution Y must be a <em>weak acid </em>only!
The number of protons in the nucleus of the atom is equal to the atomic number. The number of electrons in a neutral atom is equal to the number of protons. The mass number of the atom is equal to the sum of the number of protons and neutrons in the nucleus.
Hope it helped
Answer:
0.675 mol
Explanation:
Step 1: Write the balanced equation
2 Al + Fe₂O₃ ⇒ 2 Fe + Al₂O₃
Step 2: Establish the appropriate molar ratio
According to the balanced equation, the molar ratio of Fe to Al₂O₃ is 2:1.
Step 3: Calculate the moles of Al₂O₃ produced when 1.35 moles of Fe are produced
We will use the established molar ratio.
1.35 mol Fe × 1 mol Al₂O₃/2 mol Fe = 0.675 mol Al₂O₃
True!
For example:
The atomic mass of carbon is 12.011 (i think) and the weight of carbon is 12. But with C13 and C14 being a little higher, it makes the average higher. Random fact: C14 is used for carbon dating.
Hi!
<u>HCl is the limiting reactant.</u>
From the equation, we understand that 1 mole of Mg(OH)2 will react with 2 moles of HCl for the reaction to be complete. To find the limiting reactant we need to see which molecule is in lower quantity (in terms of moles and not mass)
Calculating the number of moles of Mg(OH)2 given
Using the formula, number of moles= mass / molecular mass
number of moles = 50.6 / 58 = ~ 0.872
Calculating the number of moles of HCl given
Number of moles = 45 / 36.5 = ~ 1.232
There are several ways to use this information to calculate the limiting reactant. In our case, we can subtract the number of moles of Mg(OH)2 from the number of moles of HCl and check for the remainder.
If it is more than 0.872, then HCl would be in excess, with Mg(OH)2 being the limiting reactant; however, if the remainder is less than 0.872, it would mean <em>HCl is the limiting reactant.</em>
1.232- 0.872 = 0.36
As 0.36 < 0.872 , we see that HCl is the limiting reagent.
NOTE: this is in the case that the moles of HCl needed to complete the reaction is twice that of Mg(OH)2.
Hope this helps!
