Let's find the electron configuration of each atom
Atom atomic number electron configuration
Bo 5 1s2 2s2 2p
F 9 1s2 2s2 2p5
Na 11 1s2 s2 2p6 3s
K 19 1s2 2s2 2p6 3s2 3p6 4s
The spherically shaped orbitals are the s orbitals.
You can se in the table that I wrote above that sodium has 2 electrons at 1s, 2 electrons at 2s and 1 electron at 3s orbitals, that is a total of five electrons at s (spherically shaped orbtials).
So the answer is the option A) sodium.
570/8.5=67.0 58... you only have to take the natural part, si the answer is 67 students
Answer:
20.79 kilojoules
Explanation:
Using Q = m×c×∆T
Where;
Q = Quantity of heat (J)
c = specific heat capacity of solid DMSO (1.80 J/g°C)
m = mass of DMSO
∆T = change in temperature
According to the provided information, m= 50g, initial temperature = 19.0°C, final temperature= 250.0°C
Q = m×c×∆T
Q = 50 × 1.80 × (250°C - 19°C)
Q = 90 × 231
Q = 20790 Joules
To convert Joules to kilojoules, we divide by 1000 i.e.
20790/1000
= 20.79 kilojoules
Hence, 20.79 kilojoules of energy is required to convert 50.0 grams of solid DMSO to gas.
Answer: The weight/weight % or percent by mass of the solute is 5.41 %.
Explanation:
Mass of the sodium sulfate,w = 9.74 g
Volume of the water = 165 mL
Density of the water = 1 g/mL
Mass of the water =
Mass of the solution, W:
Mass of solute + Mass of solvent =9.47 g + 165 g=174.47 g
The weight/weight % or percent by mass of the solute is 5.41 %.
Because there are many numbers of the human measurement . we must manage the uncertainly doing calculations because we can know what we are calculating.
