In a solution of KBr and water; KBr is the solute and water is the solvent;
Therefore; to achieve 3% by mass; it means we are going to have 3% of the mass being the solute and the other 97 % being the solvent.
Thus; KBr (solute) = 3/100 × 300 (total mass) = 9 g
Hence; the appropriate masses will be; 9.00 g of KBr and 291 g of water.
Answer:
Carbon dioxide
Explanation:
Neither helium nor carbon dioxide has a molecular dipole, so their strongest van der Waals attractive forces are London forces.
Helium is a small spherical atom with only a two electrons, so its atoms have quite weak attractions to each other.
CO₂ is a large linear molecule. It has more electrons than helium, so the attractive forces are greater. Furthermore, the molecules can align themselves compactly side-by-side and maximize the attractions (see below).
For example. CO₂ becomes a solid at -78 °C, but helium must be cooled to -272 °C to make it freeze (that's just 1 °C above absolute zero).
Answer:
The empirical formula is CH2O, and the molecular formula is some multiple of this
Explanation:
In 100 g of the unknown, there are 40.0⋅g12.011⋅g⋅mol−1 C; 6.7⋅g1.00794⋅g⋅mol−1 H; and 53.5⋅g16.00⋅g⋅mol−1 O.
We divide thru to get, C:H:O = 3.33:6.65:3.34. When we divide each elemental ratio by the LOWEST number, we get an empirical formula of CH2O, i.e. near enough to WHOLE numbers. Now the molecular formula is always a multiple of the empirical formula; i.e. (EF)n=MF.So 60.0⋅g⋅mol−1=n×(12.011+2×1.00794+16.00)g⋅mol−1.Clearly n=2, and the molecular formula is 2×(CH2O) = CxHyOz.
Answer:
The net ionic equation for the given reaction :
Explanation:
...[1]
..[2]
...[3]
Replacing 
, NaI and 
in [1] by usig [2] [3] and [4]
Removing the common ions present ion both the sides, we get the net ionic equation for the given reaction [1]:
