A neutral atom of potassium has 19 electrons.
Answer:
d.) granulated
Because the granulated sugar has a greater surface area.
First gap is BY USING MAGNETS
2nd is ELECTROLYSIS
3rd is EVAPORATION
Answer:
A. it contains a lot of matter
Answer:
1.208x10⁻³M and 392.5ppm La(NO3)3
Explanation:
The reaction that occurs is:
La2O3 + 6HNO3 → 2La(NO3)3 + 3H2O
Molarity is defined as the moles of solute (In this case, LaO3) per liter of solution. And ppm, are mg of solute per liter of solution.
To solve this question we must find the moles of La(NO3)3 produced and its mass in milligrams to find molarity and ppm:
<em>Moles La2O3 -Molar mass: 325.81g/mol-</em>
0.1968g * (1mol / 325.81g) = 6.04x10⁻⁴ moles La2O3
<em>Moles La(NO3)3:</em>
6.04x10⁻⁴ moles La2O3 * (2mol La(NO3)3 / 1mol La2O3) = 1.208x10⁻³ moles La(NO3)3
<em>Molarity:</em>
1.208x10⁻³ moles La(NO3)3 / 1L =
<h3>1.208x10⁻³M</h3>
<em>Mass La(NO3)3 -Molar mass: 324.92g/mol-</em>
1.208x10⁻³ moles La(NO3)3 * (324.92g / mol) = 0.392.5g La(NO3)3
In mg:
392.5mg La(NO3)3 / 1L =
392.5ppm La(NO3)3
