Tag: non-metals
Questions Related to non-metals
Which of the following has highest calorific value?
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Animal fat
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Hydrogen gas
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Gasoline
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Coal
Animal fat: 38kJ/g
Coal: 29.3kJ/g
Hydrogen gas: 142kJ/g
Gasoline: 48kJ/g
The usage of dihydrogen is:
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It acts a a fuel cell
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Energy is distributed in the form of dihydrogen
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It is economical fuel
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All of the above
Dihydrogen fuel is a zero-emission fuel when burned with oxygen (if one considers water not as an emission) or used in a contained cell. The energy released enables hydrogen to act as a fuel. In an electrochemical cell, that energy can be used with relatively high efficiency.
How many atoms of oxygen are present in the compound $ K _4Al _2 (SO _4) _3.24H _2O? $
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40
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36
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32
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31
Hydrogen gas is:
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has high molecular weight.
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a medium for storage of energy
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excellent fuel
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both B and C
Hydrogen is not found in pure form on Earth, however, so it must be produced from other compounds such as natural gas, biomass, alcohols or water. In all cases it takes energy to convert these into pure hydrogen. For that reason, hydrogen is really an energy carrier or storage medium rather than an energy source in itself.
Basic principle of hydrogen economy is:
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transportation of energy in the form of liquid or gaseous dihydrogen
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storage of energy in the form of liquid or gaseous dihydrogen
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both $A$ and $B$
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none of the above
The usage of hydrogen as a low-carbon energy source, such as gasoline as a transport fuel, it is referred to as "Hydrogen economy". The basic principles of Hydrogen economy are:-
The mass number of oxygen atom is:
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16
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8
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12
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10
Atomic number = number of protons = 8
Number of neutrons = 8
Mass number = number of protons + number of neutrons
So mass number of oxygen = 16
Dissolved air contains a higher percentage of oxygen than ordinary air.
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True
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False
Dissolved air has a higher percentage of oxygen as compared to ordinary air. Air dissolved in water contains 36% oxygen as compared to 21% in air. This is because oxygen in the air has a higher solubility than other elements in air and also there is hydrogen bonding between water and oxygen that increases its solubility.
Which statement is false?
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Elements of VB group are transition elements
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Elements of VA group are all metalloids
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Elements of IA and IIA groups are metals
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Elements of IVA group are neither strongly electronegative nor strongly electropositive
In element of $VA$ only arsenic and antimony are metalloids where as nitrogen and phosphorus are non metal. Bismuth and moscovium are metal.
______ is the metal which was first discovered by man.
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Bronze
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Silver
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Iron
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Copper
Copper is a metal which was first discovered by man.
Which of the following is the most reactive metal?
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Copper
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Gold
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Silver
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Francium
Francium, right on the bottom of the group one of periodic table. As we know,size of the atoms increases as you go down a column and decreases as you go across the table. The larger the atom, the easier is to get rid of the valence electrons and easier to react with other atoms. Now if you look at the periodic table, francium has the largest radius therefore it is the most reactive element.