Answer:
b. halogens
Explanation:
The elements of group 17 are called halogens. These are six elements Fluorine, Chlorine, Bromine, Iodine, Astatine. Halogens are very reactive these elements cannot be found free in nature. Their chemical properties are resemble greatly with each other. As we move down the group in periodic table size of halogens increases that's way fluorine is smaller in size as compared to other halogens elements. Their boiling points also increases down the group which changes their physical states.
<u>Answer:</u> The
for the reaction is -120.9 kJ.
<u>Explanation:</u>
Hess’s law of constant heat summation states that the amount of heat absorbed or evolved in a given chemical equation remains the same whether the process occurs in one step or several steps.
According to this law, the chemical equation is treated as ordinary algebraic expressions and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is equal to the sum of the enthalpy changes of the intermediate reactions.
The given chemical reaction follows:

The intermediate balanced chemical reaction are:
(1)
(2)
( × 3)
(3)
( × 2)
The expression for enthalpy of the reaction follows:
![\Delta H^o_{rxn}=[1\times (-\Delta H_1)]+[3\times \Delta H_2]+[2\times \Delta H_3]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Brxn%7D%3D%5B1%5Ctimes%20%28-%5CDelta%20H_1%29%5D%2B%5B3%5Ctimes%20%5CDelta%20H_2%5D%2B%5B2%5Ctimes%20%5CDelta%20H_3%5D)
Putting values in above equation, we get:
![\Delta H^o_{rxn}=[(1\times -(-2026.6))+(3\times (-393.5))+(2\times (-483.5))]=-120.9kJ](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Brxn%7D%3D%5B%281%5Ctimes%20-%28-2026.6%29%29%2B%283%5Ctimes%20%28-393.5%29%29%2B%282%5Ctimes%20%28-483.5%29%29%5D%3D-120.9kJ)
Hence, the
for the reaction is -120.9 kJ.
Answer:
The density of block is 2 g/mL.
Explanation:
Density:
Density is equal to the mass of substance divided by its volume.
Units:
SI unit of density is Kg/m3.
Other units are given below,
g/cm3, g/mL , kg/L
Formula:
D=m/v
D= density
m=mass
V=volume
Symbol:
The symbol used for density is called rho. It is represented by ρ. However letter D can also be used to represent the density.
Given data:
mass of block = 12 g
volume = 6 mL
density = ?
Now we will put the values in the formula,
d= m/v
d = 12 g/ 6 mL
d = 2 g/mL
so, the density of block is 2 g/mL .
Answer:
rotor
Explanation:
The part of the motor being pointed to is called the <em>rotor</em>.
Answer:
c) It describes the affinity an atom has for an electron.
Explanation:
C quite literally describes what electronegativity is, you can rule out most others by looking at periodic trends as attached below.