Butane: It is an organic compound belongs to class of alkane having molecular formula .
Butane consist of four carbon and ten hydrogen atoms attached by single covalent bond. Carbon and hydrogen atoms are attached in such a way that the valency of carbon that is four and valency of hydrogen that is one is completely satisfied and thus, results in the formation of stable compound.
The structure of butane with hydrogen atoms is shown in the image.
Answer:
II and IV.
Explanation:
I. (INCORRECT). A model is a tentative to determinate a thing that can't be proved, and it's made based on evidence. If the model can explain the observation in nature, it is considered right, although it can be proved by a theory.
II. (CORRECT). The most accepted model of atoms says that they're formed by tiny particles, protons, neutrons, and electrons, with the first two on the nucleus, and the other surrounding it in an open space.
III. (INCORRECT). A heterogeneous mixture is a mixture of substances that is possible to identify phases of them, such as in oil and water. In the air, isn't possible to identify the constituents, and it's a homogeneous mixture.
IV. (CORRECT). Silver has atomic number 47, which is its number of protons. The atomic mass is the sum of protons and neutrons, so the number of neutrons is 108 - 47 = 61.
Hey there !
a) Pb(SO4)2 => <span> lead(II) sulfate
b) </span><span>The molar mass of this compound was calculated from the amount of atoms of each element, with its respective atomic masses
Pb = 207.2 a.m.u
S = 32.065 a.m.u
O = </span><span>15.9994 a.m.u
Therefore:
</span>Pb(SO4)2 = 207.2 + 32.065 * 2 + 15.9994 * 8 => <span>399.3252 g/mol
</span>
hope this helps!
A covalent bond is a chemical bond, they form when two atoms or more share an electron.