A metalloid is an element that has properties that are intermediate between those of metals and nonmetals. Metalloids can also be called semimetals. On the periodic table, the elements colored yellow, which generally border the stair-step line, are considered to be metalloids.
In an average mass, each entry has equal weight. In a weighted average, we multiply each entry by a number representing its relative importance.
Assume that your class consists of 15 girls and 5 boys. Each girl has a mass of 54 kg, and each boy has a mass of 62 kg.
<em>Average mass</em> = (girl + boy)/2 = (54 kg + 62 kg)/2 = <em>58 kg</em>
<em>Weighted average (Method 1)
</em>
Use the <em>numbers of each</em> gender (15 girls + 5 boys)
,
Weighted average = (15×54 kg + 5×62 kg)/20 = (810 kg + 310 kg)/20
= 1120 kg/20 = <em>56 kg</em>.
If you put all the students on one giant balance, their total mass would be
1120 kg and the average mass of a student would be <em>56 kg.
</em>
<em>Weighted average (Method 2)
</em>
Use the <em>relative percentages</em> of each gender (75 % girls and 25 % boys).
Weighted average = 0.75×54 kg + 0.25×62 kg = 40.5 kg + 15.5 kg = <em>56 kg</em>
Each girl contributes 40.5 kg and each boy contributes 15.5 kg to the <em>weighted average</em> mass of a student.
Answer:
Liming reagent in the given reaction is oxygen.
Explanation:
Mass of octane = 12.85 g
Mass of oxygen = 7.46 g
Molar mass of octane = 114.23 g/mol
Molar mass of oxygen = 32
According to the reaction, 2 moles of octane requires 25 moles of O2
so, 0.1125 moles of octane requires 
of oxygen.
but only 0.2331 mol of oxygen is present.
Hence, oxygen is the limiting reagent
Answer:
Atomos, molecules, ions or radicals.
Explanation:
An elementary reaction always formed by chemical species, i mean atomos, molecules, ions or radicals.
