The element has 83 electrons
Homeostasis is the ability to maintain stable internal conditions B is the answer
Answer:
63.05% of MgCO3.3H2O by mass
Explanation:
<em>of MgCO3.3H2O in the mixture?</em>
The difference in masses after heating the mixture = Mass of water. With the mass of water we can find its moles and the moles and mass of MgCO3.3H2O to find the mass percent as follows:
<em>Mass water:</em>
3.883g - 2.927g = 0.956g water
<em>Moles water -18.01g/mol-</em>
0.956g water * (1mol/18.01g) = 0.05308 moles H2O.
<em>Moles MgCO3.3H2O:</em>
0.05308 moles H2O * (1mol MgCO3.3H2O / 3mol H2O) =
0.01769 moles MgCO3.3H2O
<em>Mass MgCO3.3H2O -Molar mass: 138.3597g/mol-</em>
0.01769 moles MgCO3.3H2O * (138.3597g/mol) = 2.448g MgCO3.3H2O
<em>Mass percent:</em>
2.448g MgCO3.3H2O / 3.883g Mixture * 100 =
<h3>63.05% of MgCO3.3H2O by mass</h3>
Answer:
1140 mmHg
Explanation:
1 atmosphere is 760 mmHg, so 1.5 atmospheres is ...
1.5×760 mmHg = 1140 mmHg
Answer:
molarity= 0.238 mol L-
Explanation:
The idea here is that you need to use the fact that all the moles of sodium phosphate that you dissolve to make this solution will dissociate to produce sodium cations to calculate the concentration of the sodium cations.
Na 3 PO 4 (aq) → Na + (aq) + PO3−4 (aq)
Use the molar mass of sodium phosphate to calculate the number of moles of salt used to make this solution.
3.25g⋅1 mole N 3PO4 163.9g = 0.01983 moles Na3 PO 4
Now, notice that every
1 mole of sodium phosphate that you dissolve in water dissociates to produce
3bmoles of sodium cations in aqueous solution.
