Answer:
Explanation:
a) In an exothermic reaction, the energy transferred to the surroundings from forming new bonds is ___more____ than the energy needed to break existing bonds.
b) In an endothermic reaction, the energy transferred to the surroundings from forming new bonds is ___less____ than the energy needed to break existing bonds.
c) The energy change of an exothermic reaction has a _____negative_______ sign.
d) The energy change of an endothermic reaction has a ____positive________ sign.
The energy changes occur during the bonds formation and bonds breaking.
There are two types of reaction endothermic and exothermic reaction.
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:
Value = 1.80 g/cm³ (Approx)
Explanation:
Given:
![\frac{3.39 \times 10^7g}{(\frac{4}{3} )(3.1416)(1.65 \times 10^2 cm)^3}](https://tex.z-dn.net/?f=%5Cfrac%7B3.39%20%5Ctimes%2010%5E7g%7D%7B%28%5Cfrac%7B4%7D%7B3%7D%20%29%283.1416%29%281.65%20%5Ctimes%2010%5E2%20cm%29%5E3%7D)
Computation:
![\frac{3.39 \times 10^7g}{(\frac{4}{3} )(3.1416)(1.65 \times 10^2 cm)^3} \\\\\frac{3.39 \times 10^7g}{(\frac{4}{3} )(3.1416)(4.492125 \times 10^6 cm^3)} \\\\ \frac{3.39 \times 10^7g}{(\frac{4}{3} )(3.1416)(4.492125 \times 10^6 cm^3)}\\\\ \frac{3.39 \times 10^7g}{18.8166132\times 10^6 cm^3} \\\\ 1.80159945g/cm^3](https://tex.z-dn.net/?f=%5Cfrac%7B3.39%20%5Ctimes%2010%5E7g%7D%7B%28%5Cfrac%7B4%7D%7B3%7D%20%29%283.1416%29%281.65%20%5Ctimes%2010%5E2%20cm%29%5E3%7D%20%5C%5C%5C%5C%5Cfrac%7B3.39%20%5Ctimes%2010%5E7g%7D%7B%28%5Cfrac%7B4%7D%7B3%7D%20%29%283.1416%29%284.492125%20%5Ctimes%2010%5E6%20cm%5E3%29%7D%20%5C%5C%5C%5C%20%5Cfrac%7B3.39%20%5Ctimes%2010%5E7g%7D%7B%28%5Cfrac%7B4%7D%7B3%7D%20%29%283.1416%29%284.492125%20%5Ctimes%2010%5E6%20cm%5E3%29%7D%5C%5C%5C%5C%20%5Cfrac%7B3.39%20%5Ctimes%2010%5E7g%7D%7B18.8166132%5Ctimes%2010%5E6%20cm%5E3%7D%20%5C%5C%5C%5C%201.80159945g%2Fcm%5E3)
Value = 1.80 g/cm³ (Approx)
Since an acidic salt solution is produced when a strong acid neutralizes a weak base, the pH of the salt solution formed when HCl is added to R2NH will be less than 7.
<h3>What is a neutralization reaction?</h3>
A neutralization reaction is the react ion between an acid and a base to form salt and water only.
Neutralization reactions can either produce a neutral solution, an acidic solution or an alkaline solution at equivalence point.
When a strong acid is added to a weak base, the pH of the salt solution formed will be less than 7.
Therefore, the pH of the salt solution formed when HCl is added to R2NH will be less than 7.
Learn more about pH at: brainly.com/question/940314
Answer: n=15.56moles
Explanation:
PV = nRT
where
P is pressure in atmospheres
V is volume in Liters
n is the number of moles of the gas
R is the ideal gas constant = given as (0.0821L -atm/k-mol
PV = nRT
n= PV/RT
n= (1.5 X 230)/ (0.0821 X 270)
n= 15.56 moles
Answer:
Maybe or maybe not (not sure)
Explanation:
A displacement reaction is a type of reaction where one element is displaced by another from a compound.
In the case of magnesium and lead nitrate, magnesium is more reactive than lead. Therefore, it will displace lead from lead nitrate to form magnesium nitrate and lead.
The reaction can be represented as:
Mg(s) + Pb(NO3)2(aq) → Mg(NO3)2(aq) + Pb(s)
Another answer could be;
A displacement reaction does not take place in 'magnesium + lead nitrate' because magnesium is more reactive than lead.