Answer: Option D is the correct answer.
Explanation: A carbon atom is a group 14 element that has atomic number 6. In order to attain stability carbon atom needs to be bonded to four electrons of another atom. A carbon atom usually bonds with another atom by sharing of electrons.
Answer:
is an electric force on the potassium ion due to the chloride ion.
Explanation:
Charge on potassium ion = ![q_1=1.602\times 10^{-19} C](https://tex.z-dn.net/?f=q_1%3D1.602%5Ctimes%2010%5E%7B-19%7D%20C)
Charge on chlorine ion = ![=q_2=-1.602\times 10^{-19} C](https://tex.z-dn.net/?f=%3Dq_2%3D-1.602%5Ctimes%2010%5E%7B-19%7D%20C)
Separation between these two charges = r = ![7.700 nm=7.700\times 10^{-9} m](https://tex.z-dn.net/?f=7.700%20nm%3D7.700%5Ctimes%2010%5E%7B-9%7D%20m)
![1 nm=10^{-9} m](https://tex.z-dn.net/?f=1%20nm%3D10%5E%7B-9%7D%20m)
Electric force on the potassium ion due to the chloride ion = F
Coulomb's law is given as ;
![F=K\times \frac{q_1\times q_2}{r^2}](https://tex.z-dn.net/?f=F%3DK%5Ctimes%20%5Cfrac%7Bq_1%5Ctimes%20q_2%7D%7Br%5E2%7D)
= Charges on both charges
r = distance between the charges
K = Coulomb constant =![9\times 10^{9} N m^2/C^2](https://tex.z-dn.net/?f=9%5Ctimes%2010%5E%7B9%7D%20N%20m%5E2%2FC%5E2)
![F=9\times 10^{9} N m^2/C^2\times \frac{1.602\times 10^{-19} C\times (-1.602\times 10^{-19} C)}{(7.700\times 10^{-9} m)^2}](https://tex.z-dn.net/?f=F%3D9%5Ctimes%2010%5E%7B9%7D%20N%20m%5E2%2FC%5E2%5Ctimes%20%5Cfrac%7B1.602%5Ctimes%2010%5E%7B-19%7D%20C%5Ctimes%20%28-1.602%5Ctimes%2010%5E%7B-19%7D%20C%29%7D%7B%287.700%5Ctimes%2010%5E%7B-9%7D%20m%29%5E2%7D)
![F=-3.896\times 10^{-12} N](https://tex.z-dn.net/?f=F%3D-3.896%5Ctimes%2010%5E%7B-12%7D%20N)
(negative sign indicates that attractive force is exerting between two ions)
is an electric force on the potassium ion due to the chloride ion.
<span>13.7 g
The balanced formula is:
Pb(ClO3)2(aq)+2NaI(aq) ==> PbI2(s) + 2NaClO3(aq)
The number of moles of NaI we have is the volume of fluid multiplied by the molarity so
0.350 * 0.170 = 0.0595 moles
Since the NaI is the limiting reactant, for every two moles used, we'll produce 1 mole of precipitate. So
0.0595 mole / 2 = 0.02975 mole
Now we need to calculate the molar mass of PbI2. Looking up the atomic weights
Atomic weight Lead = 207.2
Atomic weight iodine = 126.90447
Molar mass PbI2 = 207.2 + 2 * 126.90447 = 461.00894 g/mol
Now multiply the molar mass by the number of moles we have.
461.00894 g/mol * 0.02975 mol = 13.71501597 g
Rounded to 3 significant figures, the answer is 13.7 g</span>
Answer:
(b) gas and dust
Explanation:
"The interstellar medium is the stuff between the stars. Made up mostly of hydrogen and helium gas – plus trace amounts of ices, silicate grains, and all the other elements – it contains all the material needed to make stars and planets. It is shaped by stellar winds, dying stars, galactic magnetic fields, and supernova explosions."
"The interstellar medium is filled primarily with hydrogen gas. A relatively significant amount of helium has also been detected, along with smaller percentages of such substances as calcium, sodium, water, ammonia, and formaldehyde . Sizable quantities of dust particles of uncertain composition are present as well."
<span>The key difference between Mendeleev and modern periodic table is that Mendeleev’s periodic table was based on the increasing atomic masses while the modern periodic table is based on the increasing atomic numbers. Let us see here what is Mendeleev periodic table and what is modern periodic table, and then compare both to understand the difference between both periodic tables. Mendeleev is the pioneer of the modern periodic table, though a numerous number of changes had been made to the old version of the periodic table. Both of these attempts are equally important to the scientific community; because without an invention of the periodic relationship in elements, the modern developments in Science would not reach a development era as today. Before the invention of Mendeleev’s classification, there were several attempts made by several chemists, but their periodic laws were inadequate to apply for all the elements. The modern periodic table is so advantageous for the development in the Science.</span>