11959
Two elements \(X\) and \(Y\) have following electron configurations\(X\) \( = 1{s^2},\,\,2{s^2}2{p^6},\,\,3{s^2}3{p^6},\,\,4{s^2}\)and \(Y\) \( = 1{s^2},\,\,2{s^2}2{p^6},\,\,3{s^2}3{p^5}\)The compound formed by combination of \(X\) and \(Y\) is
1 \(X{Y_5}\)
2 \({X_2}{Y_5}\)
3 \({X_5}{Y_3}\)
4 \(X{Y_2}\)
Explanation:
Electronic configuration of \(X\) is: \(X =1 s ^2\, 2 s ^2\, 2 p ^6\, 3 s ^2 \,3 p ^6\, 4 s ^2\) has \(2\) electrons more than stable configuration. So this can be written as \(X ^{2+}\) after removing \(2\) eletrcons. Electronic configuration of \(Y\) is: \(Y=1 s^2\, 2 s^2\, 2 p^6\, 3 s^2 \,3 p^5\) has \(1\) electron less than stable configuration. So this can be written as \(Y ^{-}\) after gaining \(1\) electron \(X ^{2+}+2 Y ^{-}= XY _2\) \(2\) ions of element \(Y\) combine with \(1\) ion \(X\) to give \(XY _2\). The resulting molecule will be stable and will have no net charge.
Chemical Bonding and Molecular Structure
11960
Covalent compounds have low melting point because
1 Covalent bond is less exothermic
2 Covalent molecules have definite shape
3 Covalent bond is weaker than ionic bond
4 Covalent molecules are held by weak Vander Waal's force of attraction
Explanation:
The melting and the boiling points of covalent compounds are generally low because of the weak Van der Waals forces and so can be easily converted from liquid to gas or from solid to liquid.
Chemical Bonding and Molecular Structure
11961
\(p\) and \(n-\)type of semiconductors are formed due to
1 Covalent bonds
2 Metallic bonds
3 Ionic bonds
4 Co-ordinate bond
Explanation:
Pentavalent impurities Impurity atoms with \(5\) valence electrons produce \(n-\) type semiconductors by contributing extra electrons. Trivalentimpurities Impurity atoms with \(3\) valence electrons produce \(p\) - type semiconductors by producing a "hole" or electron deficiency. The trivalent and pantavalent atoms need an additional electron to form covalent bonds.
Chemical Bonding and Molecular Structure
11962
Which of the following is Lewis acid
1 \(B{F_3}\)
2 \(N{H_3}\)
3 \(P{H_3}\)
4 \(S{O_2}\)
Explanation:
(a) \(B{F_3}\) contain \(6\) electron so it is lewis acid.
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Chemical Bonding and Molecular Structure
11959
Two elements \(X\) and \(Y\) have following electron configurations\(X\) \( = 1{s^2},\,\,2{s^2}2{p^6},\,\,3{s^2}3{p^6},\,\,4{s^2}\)and \(Y\) \( = 1{s^2},\,\,2{s^2}2{p^6},\,\,3{s^2}3{p^5}\)The compound formed by combination of \(X\) and \(Y\) is
1 \(X{Y_5}\)
2 \({X_2}{Y_5}\)
3 \({X_5}{Y_3}\)
4 \(X{Y_2}\)
Explanation:
Electronic configuration of \(X\) is: \(X =1 s ^2\, 2 s ^2\, 2 p ^6\, 3 s ^2 \,3 p ^6\, 4 s ^2\) has \(2\) electrons more than stable configuration. So this can be written as \(X ^{2+}\) after removing \(2\) eletrcons. Electronic configuration of \(Y\) is: \(Y=1 s^2\, 2 s^2\, 2 p^6\, 3 s^2 \,3 p^5\) has \(1\) electron less than stable configuration. So this can be written as \(Y ^{-}\) after gaining \(1\) electron \(X ^{2+}+2 Y ^{-}= XY _2\) \(2\) ions of element \(Y\) combine with \(1\) ion \(X\) to give \(XY _2\). The resulting molecule will be stable and will have no net charge.
Chemical Bonding and Molecular Structure
11960
Covalent compounds have low melting point because
1 Covalent bond is less exothermic
2 Covalent molecules have definite shape
3 Covalent bond is weaker than ionic bond
4 Covalent molecules are held by weak Vander Waal's force of attraction
Explanation:
The melting and the boiling points of covalent compounds are generally low because of the weak Van der Waals forces and so can be easily converted from liquid to gas or from solid to liquid.
Chemical Bonding and Molecular Structure
11961
\(p\) and \(n-\)type of semiconductors are formed due to
1 Covalent bonds
2 Metallic bonds
3 Ionic bonds
4 Co-ordinate bond
Explanation:
Pentavalent impurities Impurity atoms with \(5\) valence electrons produce \(n-\) type semiconductors by contributing extra electrons. Trivalentimpurities Impurity atoms with \(3\) valence electrons produce \(p\) - type semiconductors by producing a "hole" or electron deficiency. The trivalent and pantavalent atoms need an additional electron to form covalent bonds.
Chemical Bonding and Molecular Structure
11962
Which of the following is Lewis acid
1 \(B{F_3}\)
2 \(N{H_3}\)
3 \(P{H_3}\)
4 \(S{O_2}\)
Explanation:
(a) \(B{F_3}\) contain \(6\) electron so it is lewis acid.
11959
Two elements \(X\) and \(Y\) have following electron configurations\(X\) \( = 1{s^2},\,\,2{s^2}2{p^6},\,\,3{s^2}3{p^6},\,\,4{s^2}\)and \(Y\) \( = 1{s^2},\,\,2{s^2}2{p^6},\,\,3{s^2}3{p^5}\)The compound formed by combination of \(X\) and \(Y\) is
1 \(X{Y_5}\)
2 \({X_2}{Y_5}\)
3 \({X_5}{Y_3}\)
4 \(X{Y_2}\)
Explanation:
Electronic configuration of \(X\) is: \(X =1 s ^2\, 2 s ^2\, 2 p ^6\, 3 s ^2 \,3 p ^6\, 4 s ^2\) has \(2\) electrons more than stable configuration. So this can be written as \(X ^{2+}\) after removing \(2\) eletrcons. Electronic configuration of \(Y\) is: \(Y=1 s^2\, 2 s^2\, 2 p^6\, 3 s^2 \,3 p^5\) has \(1\) electron less than stable configuration. So this can be written as \(Y ^{-}\) after gaining \(1\) electron \(X ^{2+}+2 Y ^{-}= XY _2\) \(2\) ions of element \(Y\) combine with \(1\) ion \(X\) to give \(XY _2\). The resulting molecule will be stable and will have no net charge.
Chemical Bonding and Molecular Structure
11960
Covalent compounds have low melting point because
1 Covalent bond is less exothermic
2 Covalent molecules have definite shape
3 Covalent bond is weaker than ionic bond
4 Covalent molecules are held by weak Vander Waal's force of attraction
Explanation:
The melting and the boiling points of covalent compounds are generally low because of the weak Van der Waals forces and so can be easily converted from liquid to gas or from solid to liquid.
Chemical Bonding and Molecular Structure
11961
\(p\) and \(n-\)type of semiconductors are formed due to
1 Covalent bonds
2 Metallic bonds
3 Ionic bonds
4 Co-ordinate bond
Explanation:
Pentavalent impurities Impurity atoms with \(5\) valence electrons produce \(n-\) type semiconductors by contributing extra electrons. Trivalentimpurities Impurity atoms with \(3\) valence electrons produce \(p\) - type semiconductors by producing a "hole" or electron deficiency. The trivalent and pantavalent atoms need an additional electron to form covalent bonds.
Chemical Bonding and Molecular Structure
11962
Which of the following is Lewis acid
1 \(B{F_3}\)
2 \(N{H_3}\)
3 \(P{H_3}\)
4 \(S{O_2}\)
Explanation:
(a) \(B{F_3}\) contain \(6\) electron so it is lewis acid.
11959
Two elements \(X\) and \(Y\) have following electron configurations\(X\) \( = 1{s^2},\,\,2{s^2}2{p^6},\,\,3{s^2}3{p^6},\,\,4{s^2}\)and \(Y\) \( = 1{s^2},\,\,2{s^2}2{p^6},\,\,3{s^2}3{p^5}\)The compound formed by combination of \(X\) and \(Y\) is
1 \(X{Y_5}\)
2 \({X_2}{Y_5}\)
3 \({X_5}{Y_3}\)
4 \(X{Y_2}\)
Explanation:
Electronic configuration of \(X\) is: \(X =1 s ^2\, 2 s ^2\, 2 p ^6\, 3 s ^2 \,3 p ^6\, 4 s ^2\) has \(2\) electrons more than stable configuration. So this can be written as \(X ^{2+}\) after removing \(2\) eletrcons. Electronic configuration of \(Y\) is: \(Y=1 s^2\, 2 s^2\, 2 p^6\, 3 s^2 \,3 p^5\) has \(1\) electron less than stable configuration. So this can be written as \(Y ^{-}\) after gaining \(1\) electron \(X ^{2+}+2 Y ^{-}= XY _2\) \(2\) ions of element \(Y\) combine with \(1\) ion \(X\) to give \(XY _2\). The resulting molecule will be stable and will have no net charge.
Chemical Bonding and Molecular Structure
11960
Covalent compounds have low melting point because
1 Covalent bond is less exothermic
2 Covalent molecules have definite shape
3 Covalent bond is weaker than ionic bond
4 Covalent molecules are held by weak Vander Waal's force of attraction
Explanation:
The melting and the boiling points of covalent compounds are generally low because of the weak Van der Waals forces and so can be easily converted from liquid to gas or from solid to liquid.
Chemical Bonding and Molecular Structure
11961
\(p\) and \(n-\)type of semiconductors are formed due to
1 Covalent bonds
2 Metallic bonds
3 Ionic bonds
4 Co-ordinate bond
Explanation:
Pentavalent impurities Impurity atoms with \(5\) valence electrons produce \(n-\) type semiconductors by contributing extra electrons. Trivalentimpurities Impurity atoms with \(3\) valence electrons produce \(p\) - type semiconductors by producing a "hole" or electron deficiency. The trivalent and pantavalent atoms need an additional electron to form covalent bonds.
Chemical Bonding and Molecular Structure
11962
Which of the following is Lewis acid
1 \(B{F_3}\)
2 \(N{H_3}\)
3 \(P{H_3}\)
4 \(S{O_2}\)
Explanation:
(a) \(B{F_3}\) contain \(6\) electron so it is lewis acid.
