When measuring copper that is collected on a filter paper, the mass measurement obtained will include both the mass of the filter paper and copper.
therefore we have to find the mass of the empty filter paper before copper is on the paper.
the mass of the filter paper alone is 0.27 g
then the mass of copper and filter paper is 0.98 g
therefore to find the mass of copper alone we have to take the difference between the 2 masses
mass of copper = (mass of copper + filter paper ) - mass of filter paper
= 0.98 g - 0.27 g
mass of copper = 0.71 g
Answer: E=∆H*n= -40.6kj
Explanation:
V(CO) =15L=0.015M³
P=11200Pa
T=85C=358.15K
PV=nRT
n=(112000×0.015)/(8.314×358.15)
n(Co)= 0.564mol
V(Co)= 18.5L = 0.0185m³
P=744torr=98191.84Pa
T= 75C = 388.15k
PV=nRT
n= (99191.84×0.0185)/(8.314×348.15)
n(H2) = 0.634mol
n(CH30H) =1/2n(H2)=1/2×0.634mol
=0.317mol
∆H =∆Hf{CH3OH}-∆Hf(Co)
∆H=-238.6-(-110.5)
∆H = 128.1kj
E=∆H×n=-40.6kj.
Currently in this equation, you have 2 hydrogen atoms and 2 oxygen atoms on the left, and then 2 hydrogen atoms and 1 oxygen atom on the right. To balance, you would need to even out the oxygens, so we can first place a 2 in front of H2O to get:
H2 + O2 -> 2H2O
Now, however, you can see that we have too many hydrogen atoms on the right, so to get the final answer, we add a 2 in front of hydrogen on the left:
2H2 + O2 -> 2H2O
I hope this helps!
Answer:
Explanation: Atoms are the building blocks of all matter. They consist of three sub-atomic particles: protons, neutrons and electrons. Protons and neutrons are found in the nucleus of an atom. Electrons are found in energy levels around the nucleus as shown in the diagram representing a carbon atom with 6 protons, 6 neutrons and 6 electrons.
Sub-atomic particles
Particle Whereabouts in atom Relative mass Charge
Proton Nucleus 1 +1
Neutron Nucleus 1 0
Electron Outside the nucleus 1/1840 -1
Diagram of carbon atom - nucleus with electrons orbiting
Diagram of carbon atom - nucleus with electrons orbiting
In chemistry we are particularly interested in electrons. As you will see later, this is because chemical reactions involve the rearrangement of electrons. Nuclei of atoms (protons and neutrons) usually remain unchanged (except in radioactive decay).
Electrons are arranged in atoms according to their energies. This is called the electronic structure or electronic configuration of the atom. A crude but still useful model says the electrons can be in different energy levels. Electrons in a particular energy level all have the same energy as one another. The lowest energy level can accommodate up to 2 electrons. The second level can accommodate up to 8 electrons. The third level can accommodate up to 18 electrons. The diagram shows the situation for a sulfur atom.
Electronic configuration of sulfur including energy level diagram
Since you provide no options, Henry Moseley measured a property linked to Periodic Table position. After his revisions to the periodic table, Atomic number became more meaningful and the three pair of elements that seemed to be in the wrong order could be explained
