Answer:
Both are endothermic reactions.
Explanation:
Chemical equation:
1/2H₂(g) + 1/2I₂(g) → HI(g) + 6.2 kcal/mol
Chemical equation:
21.0 kcal/mol + C(s) + 2S(s) → CS₂
Both reaction are endothermic because heat is added in both of reactions.
Endothermic reactions:
The type of reactions in which energy is absorbed are called endothermic reactions.
In this type of reaction energy needed to break the bond are higher than the energy released during bond formation.
For example:
C + H₂O → CO + H₂
ΔH = +131 kj/mol
it can be written as,
C + H₂O + 131 kj/mol → CO + H₂
Exothermic reaction:
The type of reactions in which energy is released are called exothermic reactions.
In this type of reaction energy needed to break the bonds are less than the energy released during the bond formation.
For example:
Chemical equation:
C + O₂ → CO₂
ΔH = -393 Kj/mol
it can be written as,
C + O₂ → CO₂ + 393 Kj/mol
Answer:
0.086
Explanation:
The formula for calculating the fraction of a covalent bond can be expressed as:
= exp (-0.25ΔE²)
![= exp[-0.25(E_{Al}-E_{p})^2]---(1)](https://tex.z-dn.net/?f=%3D%20exp%5B-0.25%28E_%7BAl%7D-E_%7Bp%7D%29%5E2%5D---%281%29)
from the equation above;
= the electronegativity of aluminum
= electronegativity of phosphorus
Using the data from periodic table figures;
= 1.5
= 2.1
∴
fraction of the covalent = exp[-0.25(1.5 - 2.1)²]
fraction of the covalent = exp(-0.09)
fraction of the covalent = 0.914
Now, the fraction of ionic bond will be = 1 - the fraction of covalent bond
= 1 - 0.914
∴
the fraction of bond that is ionic = 0.086
Answer:
MgBr₂ + AgNO₃ => Mg(NO₃)₂ + AgBr
Explanation:
Find the element symbol and charge of each element on the periodic table. For polyatomic ions (nitrate), reference your polyatomic ions chart. Use the "partner's charge" rule to find the number of atoms in each compound.
Charges are written as superscripts. "1" is usually not written, just the + or - sign. The charge of silver is 1, which is the (I) bracket roman numeral 1. It is indicated like that because it is multivalent, meaning it has more than one possible charge.
<u>Write each element as an ion</u> (with the charge).
Magnesium is Mg²⁺
Bromide is Br⁻
Silver(I) is Ag⁺
Nitrate is (NO₃)⁻
<u>Write each compound.</u>
REACTANTS SIDE
Magnesium bromide
Mg²⁺Br⁻ Cross over the partner's charge. Since Br is charge 1, Mg has 1 atom. Since Mg has charge 2, Br has 2 atoms.
MgBr₂
Silver(I) nitrate
Ag⁺(NO₃)⁻
AgNO₃ Both have 1 atom because each partner's charge was 1. You do not need to write brackets if nitrate only has 1 atom.
PRODUCTS SIDE
Magnesium nitrate
Mg²⁺(NO₃)⁻
Mg(NO₃)₂ Nitrate has 2 atoms because magnesium's charge is 2.
Silver(I) bromide
Ag⁺Br⁻
AgBr Both have 1 atom.
Write the compounds into an equation. Reactants go on the left side, products go on the right side. Between the reactants and products, write an arrow.
MgBr₂ + AgNO₃ => Mg(NO₃)₂ + AgBr
Answer:
In 1827, Brown observed, using a microscope, that small particles ejected from pollen grains suspended in water executed a kind of continuous and jittery movement, this was named “Brownian motion”. ... This random movement of particles suspended in a fluid is now called after him.
Explanation:
HOPE this helps :)
Answer:
These four subsystems are called "spheres." Specifically, they are the "lithosphere" (land), "hydrosphere" (water), "biosphere" (living things), and "atmosphere" (air). Each of these four spheres can be further divided into sub-spheres.
Explanation:
These four subsystems are called "spheres." Specifically, they are the "lithosphere" (land), "hydrosphere" (water), "biosphere" (living things), and "atmosphere" (air). Each of these four spheres can be further divided into sub-spheres.
