Answer:
Na
Explanation:
sodium has mass number 23 and atomic number 11 so number of protons =number of electrons =atomic number which is 11 and number of neutrons=mass number-number of protons =23-11=12
HCl and NaOH react in a 1:1 ratio, meaning that 1 H+ from HCl will react with 1 OH- from NaOH. Knowing this, and that molarity is mol/liter, all we need to do is use what we have available. First we must find the mols of HCl in our solution, so we set up the following equation in the following steps:
1. 24.75mL x (0.359mol NaOH / 1000mL) = 8.885 x 10^-3mol NaOH
This is done in order to find the mols of NaOH to convert to mols of HCl.
2. 8.885x10^-3mol NaOH x (1 mol HCl/1mol NaOH) = 8.885 x 10^-3mol HCl
Here we just used the mols of NaOH we found to convert to mols of HCl using the 1:1 ratio described earlier.
From the mols of HCl all we have to do is divide by the amount of liters in the solution. Since we started with 10mL HCl and added 24.75mL NaOH, the total volume is 34.75mL = 0.03475L. So:
8.885 x 10^-3mol HCl/0.03475L = 2.557 x 10^-1M HCl
However, this is the molarity of the HCl and NaOH solution, not the original HCl solution. Using the dilution equation M1V1=M2V2, we can solve for the original molarity.
M1 = the molarity of our HCl in the titrated mixture (2.557 x 10^-1M HCl)
V1 = the total volume that our mixture has (34.75mL = 0.03475L)
M2 = what we're trying to find
V2 = the amount of the original HCl that we had (10mL = 0.010L)
Simply solving for M2 gives us:
M2 = (M1V1) / V2 or:
M2=((2.557 x 10^-1) x 0.03475L) / 0.010L = 8.89 x 10^-1M HCl. That is your answer.
Answer:
Caesium atoms will form positively charged ions.
Explanation:
Due to them having one electron in their outer orbit, it is very likely that they will give that electron away to form an octet and become stable. Hence, since they lose an electron, they lose a negative charge, and in comparison to their former non-ion self, they have gained a positive charge.
Hence, they will form positively charged ions.
Hope this helped!
Answer:
which formula can be used to calculate the molar mass of hydrogen peroxide (H2O2)?
» <u>d.2 x molar mass of H + 2 x molar mass of O</u>
Explanation:
Since we've two hydrogen atoms and two oxygen atoms, we multiply each mass by 2
Which of the following statements best defines the actual yield of a reaction?
»<u> </u><u>d.The ratio of measured yield over stoichiometric yield</u>
Answer:
0.0907 s
Explanation:
This an Arrhenius equation problem, so you relate the half-life with the kinetic constant of the reaction in order to calcule the same thermodynamic parameters at another temperature.
To calcule the kinetic constant of the reaction you need to know the order of it, look closely to the sentence "The value of the half-life is independent of the inital concentration of N2O present." the only order independent from the initial concentration of reagents is first order, so you can calculate K at 800 K, using:
Now you can use Arrhenius equation to calcule K at 1150.66 K
Then calculate the new half-life:
