Answer:
Explanation:
All three lighter boron trihalides, BX3 (X = F, Cl, Br), form stable adducts with common Lewis bases. Their relative Lewis acidities can be evaluated in terms of the relative exothermicities of the adduct-forming reaction. Such measurements have revealed the following sequence for the Lewis acidity: BF3 < BCl3 < BBr3 (in other words, BBr3 is the strongest Lewis acid).
This trend is commonly attributed to the degree of π-bonding in the planar boron trihalide that would be lost upon pyramidalization (the conversion of the trigonal planar geometry to a tetrahedral one) of the BX3 molecule, which follows this trend: BF3 > BCl3 > BBr3 (that is, BBr3 is the most easily pyramidalized). The criteria for evaluating the relative strength of π-bonding are not clear, however. One suggestion is that the F atom is small compared to the larger Cl and Br atoms, and the lone pair electron in the 2pzorbital of F is readily and easily donated, and overlaps with the empty 2pz orbital of boron. As a result, the [latex]\pi[/latex] donation of F is greater than that of Cl or Br. In an alternative explanation, the low Lewis acidity for BF3 is attributed to the relative weakness of the bond in the adducts F3B-L.
Answer: 1.56 ATM
Explanation: if we assume temperature is constant, gas obeys
Boyles law pV= constant. Then p1·V1= p2·V2. And V1 = p2V2/p1
= 3.0 atm·0,52 l / 1.0 atm
a method of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.
Answer:
B. CaCl + LiCO3 yields CaCO3 + LiCl is not correct
It should be CaCl2 + Li2CO3 → 2LiCl + CaCO3
Explanation:
For a reaction to be double displacement reaction there are two things we need to look for
1) There must be an interchange of the group of ions
2) The reactants must dissolve in water to release ions
A. 2RbNO3 + BeF2 yields Be(NO3)2 + 2RbF
2Rb+ + NO3- + Be^2+ + 2F- → Be(NO₃)₂ + 2RbF
This is correct
B. CaCl + LiCO3 yields CaCO3 + LiCl
This is not correct
The correct equation is:
CaCl2 + Li2CO3 → Ca2+ + 2Cl- + 2Li+ + CO3^2- → 2LiCl + CaCO3
C. Na3PO4 + 3KOH yields 3NaOH + K3PO4
3Na+ + PO4^3- + 3K+ + 3OH- → 3NaOH + K3PO4
This is correct
D. 2MgI2 + Mn(SO3)2 yields 2MgSO3 + MnI4
2Mg^2+ + 4I- + Mn^4+ + 2SO3^2- → 2 MgSO3 + MnI4
This is correct
