Answer:
2.2 °C/m
Explanation:
It seems the question is incomplete. However, this problem has been found in a web search, with values as follow:
" A certain substance X melts at a temperature of -9.9 °C. But if a 350 g sample of X is prepared with 31.8 g of urea (CH₄N₂O) dissolved in it, the sample is found to have a melting point of -13.2°C instead. Calculate the molal freezing point depression constant of X. Round your answer to 2 significant digits. "
So we use the formula for freezing point depression:
In this case, ΔTf = 13.2 - 9.9 = 3.3°C
m is the molality (moles solute/kg solvent)
Molality = 0.53 / 0.35 = 1.51 m
So now we have all the required data to solve for Kf:
B)
sulfur, selenium, polonium, 6
Eliminate
C)
hydrogen, fluorine, potassium, 1
D)
calcium, phosphorus, tellurium, 2
The correct option is B.
Sodium will react with elements in GROUP 6, WHICH HAVE SIX ELECTRONS IN THEIR OUTERMOST SHELLS.
Sodium is a metal with atomic number 11. The electronic configuration of sodium is 2,8,1. This implies that, sodium has one electron in its outermost shell. Sodium always donate this electron in order to become stable. Elements in group 6 have six electrons in their outermost shells and they require two more electrons to attain stability. In order to form chemical bonds with elements from group 6, two atoms of sodium will react with each atom of those elements, that is, the ratio of reaction will be 2:1. By so doing, the two sodium atoms will be the ones that will donate the two electrons that the group 6 elements need to attain stability. One example of compounds formed by such reaction is sodium sulfide, Na2S.
Answer:
B) Use a conductivity apparatus
Explanation:
I got it right on Plato. Strong acids and strong bases will conduct more than weak acids and weak bases, so you can tell if one is stronger than the other by seeing which one conducts more.