Answer:
![5.225x10^{22}atoms\ I](https://tex.z-dn.net/?f=5.225x10%5E%7B22%7Datoms%5C%20I)
Explanation:
Hello!
In this case, since 12.75 g of calcium iodide has the following number of moles (molar mass = 293.89 g/mol):
![n_{CaI_2}=12.75gCaI_2*\frac{1molCaI_2}{293.89gCaI_2}=0.0434molCaI_2](https://tex.z-dn.net/?f=n_%7BCaI_2%7D%3D12.75gCaI_2%2A%5Cfrac%7B1molCaI_2%7D%7B293.89gCaI_2%7D%3D0.0434molCaI_2)
In such a way, since 1 mole of calcium iodide contains 2 moles of atoms of iodine, and one mole of atoms of iodine contains 6.022x10²³ atoms (Avogadro's number), we compute the resulting atoms as shown below:
![atoms\ I=0.0434molCaI_2*\frac{2molI}{1molCaI_2} *\frac{6.022x10^{23}atoms\ I}{1molI} \\\\atoms\ I = 5.225x10^{22}atoms\ I](https://tex.z-dn.net/?f=atoms%5C%20I%3D0.0434molCaI_2%2A%5Cfrac%7B2molI%7D%7B1molCaI_2%7D%20%2A%5Cfrac%7B6.022x10%5E%7B23%7Datoms%5C%20I%7D%7B1molI%7D%20%5C%5C%5C%5Catoms%5C%20I%20%3D%205.225x10%5E%7B22%7Datoms%5C%20I)
Best regards!
Answer:
The answer to your question is Argon
Explanation:
Electron configuration given 1s² 2s² 2p⁶ 3s² 3p⁶
To find the element whose electron configuration is given, we can do it by two methods.
Number 1. Sum all the exponents the result will give you the atomic number of the element.
2 + 2 + 6 + 2 + 6 = 18
The element with an atomic number of 18 is Argon.
Number 2. Look at the last terms of the electronic configuration
3s² 3p⁶
Number three indicates that this element is in the third period in the periodic table.
Sum the exponents 2 + 6 = 8
Number 8 indicates that this element is the number 8 of that period without considering the transition elements.
The element with these characteristics is Argon.
1.062 mol/kg.
<em>Step 1</em>. Write the balanced equation for the neutralization.
MM = 204.22 40.00
KHC8H4O4 + NaOH → KNaC8H4O4 + H2O
<em>Step 2</em>. Calculate the moles of potassium hydrogen phthalate (KHP)
Moles of KHP = 824 mg KHP × (1 mmol KHP/204.22 mg KHP)
= 4.035 mmol KHP
<em>Step 3</em>. Calculate the moles of NaOH
Moles of NaOH = 4.035 mmol KHP × (1 mmol NaOH/(1 mmol KHP)
= 4.035 mmol NaOH
<em>Step 4</em>. Calculate the mass of the NaOH
Mass of NaOH = 4.035 mmol NaOH × (40.00 mg NaOH/1 mmol NaOH)
= 161 mg NaOH
<em>Step 5</em>. Calculate the mass of the water
Mass of water = mass of solution – mass of NaOH = 38.134 g - 0.161 g
= 37.973 g
<em>Step 6</em>. Calculate the molal concentration of the NaOH
<em>b</em> = moles of NaOH/kg of water = 0.040 35 mol/0.037 973 kg = 1.062 mol/kg
A: Na3PO4 + MnCl2 > Mn3(PO4)2 + NaCl
B. I’m sorry if I’m wrong ! Wasn’t sure about this question .