Answer:
See explanation
Explanation:
All the substances in the mixture; sodium chloride ,lead II oxide and iron filings are solids.
The first step is to use a magnet to separate the iron fillings which is a magnetizable material.
The remaining part of the mixture is now dissolved in water. Lead II oxide is insoluble in water while sodium chloride is very soluble in water hence a filtrate and a residue are obtained.
The residue is lead II oxide which can be dried to recover the solid. The filtrate contains sodium chloride which is recovered by evaporating the solution to dryness.
Answer:
15.3 %
Explanation:
Step 1: Given data
- Mass of the sample (ms): 230 g
- Mass of carbon (mC); 136.6 g
- Mass of hydrogen (mH): 26.4 g
- Mass of nitrogen (mN): 31.8 g
Step 2: Calculate the mass of oxygen (mO)
The mass of the sample is equal to the sum of the masses of all the elements.
ms = mC + mH + mN + mO
mO = ms - mC - mH - mN
mO = 230 g - 136.6 g - 26.4 g - 31.8 g
mO = 35.2 g
Step 3: Calculate the mass percent of oxygen
%O = (mO / ms) × 100% = (35.2 g / 230 g) × 100% = 15.3 %
Answer:
change in the total mass of substances
Answer:
The correct answer is 4
Explanation:
Boron trifluoride (BF₃) has a molecular geometry (as shown in the image in the question) referred to as trigonal planar; this is because each of the the fluorine atoms/molecules (bonded to the central boron atom) is placed in such a way that they form the three "end points"/"domains" of an equilateral triangle. Hence, the correct option is the last option.