Answer:
that looks pretty and also well NGC 1427A has no general shape, so it is an irregular galaxy. U has a bulge in the center and arms, so it is a spiral galaxy. They are similar in the both certain plenty of dust and gas. Both also have active star-forming sites.
First of all, there are five types of solid materials:
Metallic solids which are solids composed of metal atoms that are held together by metallic bonds.
Network solid is a chemical compound in which the atoms are bonded by covalent bonds in a continuous network extending throughout the material.
Molecular solid is a solid consisting of discrete molecules.
Ionic solid is a chemical compound composed of ions held together by electrostatic forces termed ionic bonding.
Amorphous solid is non-crystalline solid that lacks the long-range order that is characteristic of a crystal.
Now, after the defined all the types of solid materials in the equation lets to solve it.
A. the answer is the network solids, because covalent bonds are relatively strong, covalent are typically characterized by hardness, strength, and high melting points.
B. the answer is the metallic solids, due to that heat conduction occurs when a substance is heated and the particles will gain more energy vibrating more. These molecules then bump into nearby particles and transfer some of their energy to them and in metals this process have a higher probability than in the case of other solids due to the nature of the chemical bonds. It also has a range of hardness due to the strength of metallic bonds which varies dramatically.
C. the answer is the ionic solid; due to positive and negative ions which are bonded to form a crystalline solid held together by charge attractions.
Answer:
1.72 L
Explanation:
Initial Temperature of the gas T =90°+273= 363 K
Initial Volume of the gas V1= 1.41 L
Final temperature of the gas T2= 170°c +273= 443 K
Final volume of the gas V2= ????
Using Charles law;
V1/T1 = V2/T2
V1T2= V2T1
V2= V1T2/T1
V2= 1.41×443/363
V2= 1.72 L
Explanation:
From the source, The student recrystallized biphenyl by using benzene. Biphenyl is non polar and so is benzene. Biphenyl is very soluble in benzene at low as well as high temperature. Thus, it do not recrystallize as like dissolves like and gives a very poor yield.
The good recovery of the product is dependent on compound having high solubility at the high temperatures and having low solubility at the low temperatures.
Answer:
the enthalpy of the second intermediate equation is halved and has its sign changed.
Explanation:
Let us take a look at the first and second intermediate reactions as well as the overall reaction equation for the process under review;
First reaction;
Ca (s) + CO₂ (g) + ½O₂ (g) → CaCO₃ (s) ΔH₁ = -812.8 kJ
Second reaction;
2Ca (s) + O₂ (g) → 2CaO (s) ΔH₂ = -1269 kJ
Hence the overall equation is now;
CaO (s) + CO₂ (g) → CaCO₃ (s) ΔH = ?
According to the Hess law of constant heat summation, the enthalpy of the overall reaction is supposed to be obtained as a sum of the enthalpy of both reactions but this will not give the enthalpy of the overall reaction in this case. The enthalpy of the overall reaction is rather obtained by halving the enthalpy of the second intermediate reaction and reversing its sign before taking the sum as shown below;
Enthalpy of Intermediate reaction 1 + ½(- Enthalpy of Intermediate reaction 2) = Enthalpy of Overall reaction
