Covalent compounds are composed of atoms that are linked via covalent bonds i.e. bonds formed by mutual sharing of electrons. This is in complete contrast to ionic compounds which are held together by ionic bonds, i.e. bonds formed by complete transfer of electrons from one atom to the other.
In the given examples we have:
Barium nitrate: Ba(NO3)2 - Ionic
Dinitrogen tetroxide: N2O4- Covalent
Boron trifluoride: BF3-Covalent
Ammonium sulfate: (NH4)2SO4- Ionic
Carbon tetrachloride: CCl4- Covalent
Barium chloride: BaCl2 - Ionic
<span>Mixing magnesium and aluminum together produces an excellent lightweight material from which to make airplane parts. This type of mixture is called an alloy.
Alloy is a mixture of two elements, one of which is a metal.
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Answer: Correct statements are given below:
1) In activity series elements are listed according to their reactivity.
2) Nuclear reaction in which low atomic nuclei fuse to form a heavier nucleus with the release of energy. Nuclear fusion reaction occurs in the sun.
3) C3H8 + 5O2 → 3CO2 + 4H2O is the example of a combustion reaction.
4) 2Fe + O2 → 2FeO is the example of synthesis reaction. In synthesis reaction is a type of reaction in which two reactants combine to form a single product.
Well, first of all, the formula for finding potential energy is;
PE=mgh
Where; m is the mass
g is the gravitational force or acceleration due to gravity
h is the height.
Anyway, according to the question, the mass is 1kg, the acceleration due to gravity has a constant value of 10ms² . And the height is 3m. Now you just have to use all these in the formula. So;
mgh= 1 x 10 x 3. That will be 30. And the unit of potential energy is Joule. So the answer is 30 joules. Hope i helped. Have a nice day.