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.
Well - it depends on where you start and where you finish on the electromagnetic spectrum. But by most estimates, we're can see about 0.0035% of the electromagnetic spectrum (that includes gamma rays, radio waves, x-rays, infrared, ultraviolet, microwaves, etc.).
<em>Hope this helps</em>!
Answer:
H₂S + Cl₂ —> S + 2HCl
Explanation:
? + Cl₂ —> S + 2HCl
To balance the equation above, we must recognise what atoms are present in the products.
The products contains S, H and Cl.
Thus, S, H and Cl must also be present in the reactants.
Considering the equation given above, we can see clearly that H and S is missing in the reactants.
H and S together as a compound is expressed as H₂S.
Now, we shall input H₂S into the equation to obtain the complete equation. This is illustrated below:
? + Cl₂ —> S + 2HCl
H₂S + Cl₂ —> S + 2HCl
Next, we shall verify to see if the equation is balanced.
There are 2 atoms of H on both sides of the equation.
There are 2 atoms of Cl on both sides of the equation.
1 atom of S exist on both sides of the equation.
Thus, the equation is balanced.
Answer:
0.045 moles
Explanation:
Given data:
Moles of CO = ?
Volume of gas = 1 L
Temperature and pressure = standard
Solution:
The given problem will be solve by using general gas equation,
PV = nRT
P= Pressure
V = volume
n = number of moles
R = general gas constant = 0.0821 atm.L/ mol.K
T = temperature in kelvin
n = PV/RT
n = 1 atm× 1L / 0.0821 atm.L/mol.K × 273 K
n = 1 atm.L / 22.41 atm.L/mol
n = 0.045 mol
Explanation:
1) 
Energy will be absorbed by the Cs(s) to get converted into Cs(g). In order to break the strong association of particles present in solid to convert it into gaseous state energy will be needed. So, energy will be absorbed by the Cs solid in this reaction.
2) 
Energy will be absorbed by
gas in order to break bond between two Cl atoms to form isolated(alone) single chlorine atom.So, the energy will be absorbed by the chlorine gas molecule in this reaction.
3) 
Energy will be absorbed by the Cs(g) to get converted into
cation. In order to remove an electron from the outer most shell of Cs atom energy will be required by Cs atom, So, energy will be absorbed in this reaction.
4) 
Energy will get release in formation of
anion from Cl atom in gaseous state. Chlorine atom need one electron to attain noble gas configuration. So, when an electron is added to the outer most shell of chlorine it attains stability of fully filled outermost shell by which it releases energy on addition of an electron.
5) 
Energy will get release on formation of CsCl(s) from
cation and
anion. since both are oppositely charged ion and due to strong electrostatic interaction will get converted into stable molecule of CsCl (s) with release in an energy.