Thomson's atomic model is a theory about the atomic structure proposed in 1904 by Thomson, who discovered the electron in 1897, a few years before the discovery of the proton and the neutron.
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Answer : The energy required to melt 58.3 g of solid n-butane is, 4.66 kJ
Explanation :
First we have to calculate the moles of n-butane.

Given:
Molar mass of n-butane = 58.12 g/mole
Mass of n-butane = 58.3 g
Now put all the given values in the above expression, we get:

Now we have to calculate the energy required.

where,
Q = energy required
= enthalpy of fusion of solid n-butane = 4.66 kJ/mol
n = moles = 1.00 mol
Now put all the given values in the above expression, we get:

Thus, the energy required to melt 58.3 g of solid n-butane is, 4.66 kJ
Answer:
A. Yes, the substance must be water.
Explanation:
The density of a substance is unique to it. Density is defined the as the amount of substance contained per volume.
One of the ways of identifying a substance is to determine its density. Every matter is known to have their own specific densities. This makes them different from other substances. The density of gold is unique to it and it differs from that of silver.
In fact, water has density of 1.00gcm⁻³. Experimental errors and some little factors must have altered our expected figure. This a case of precision and accuracy in the experiment.
Answer:
It's 23.14 percent
Explanation:
First, the mass of all the elements are:
N = 14
O = 16
Fe = 56
In this molecule you have 3 atoms of N, and 9 atoms of O, so:
3•14 = 42
16•9 = 144
The whole mass of the molecule is:
56 + 42 + 144 = 242
242/100 = 2.42, so 1% is 2.42
56/2.42 = 23.14%