Answer:
C
Explanation:
no. of moles = no. of atoms/ Avogadro's number
0.5= N/6.02×10^23
N= 3.01×10^23
The answer is (2). The Lithium has 3 protons and 4 neutrons. For every neutral atom, it will have the same number of protons and electrons. Because the proton has one positive charge and electron has one negative charge and neutron does not have charge.
Mass = ?
Density = 2.70 g/mL
Volume = 276 mL
Therefore:
D = m / V
2.70 = m / 276
m = 2.70 x 276
m = 745.2 g
Hello!
Calvin told Marie that they could continue to add solute until the reached 40 grams because the solution was still unsaturated.
Unsaturated solutions are those in which the solvent (in this case water) can still dissolve more solute (in this case KNO₃) at the given pressure and temperature. This can be seen visually when adding more solute doesn't result in the presence of grains of solids that settle in the bottom of the flask. That happens because the rate of dissolving is higher than the rate of crystallization.
Have a nice day!
