Answer:
270 Joules
Explanation:
The specific heat capacity equation will be used for this question i.e.
Q = m. c. ΔT
Where; Q = Amount of heat
m = mass of substance
C = specific heat capacity of
substance
ΔT = change in temperature
(Final temp - initial temp)
However, for this unknown metal, we need to find the specific heat first by saying; C = Q / mΔT
Q= 135J, C=?, m= 10g, ΔT = (40-25 = 15°C)
C = 135 / 15 × 10
C = 135/150
C = 0.9 J/g°C
If the specific heat capacity of the unknown metal is 0.9 J/g°C, then at a mass of 20.0g, and a ΔT of 15°C, the amount of heat needed is:
Q = m. c. ΔT
Q = 20 × 0.9 × (40-25)
Q = 18 × 15
Q = 270J
270 Joules of heat is needed to increase the temperature of 20g of the metal from 25 - 40°C
Answer:
II) Objects made of silver become tarnished.
Explanation:
Physical properties are the properties which can be observed without changing identity of substance.
Chemical properties are the properties which describe how the substance changes into the different substance completely.
Boiling is an example of physical change in state of the substance. Color is also an example of physical property like boiling point and hence these are constants. The reason of the color is that the chromium ions shows certain colors as the electrons are excited due to absorption of the light. The tarnishing of the silver is an example of the chemical change which occurs due to the reaction of the silver with oxygen. This is also known as corrosion.
Answer:
T₂ = 859.4 K
Explanation:
Given data:
Initial volume of gas = 32.0 L
Initial temperature = 2°C (2 + 273 = 275 k)
Final temperature = ?
Final volume = 1.00 ×10²L
Solution:
The given problem will be solve through the Charles Law.
According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.
Mathematical expression:
V₁/T₁ = V₂/T₂
V₁ = Initial volume
T₁ = Initial temperature
V₂ = Final volume
T₂ = Final temperature
Now we will put the values in formula.
V₁/T₁ = V₂/T₂
T₂ = V₂T₁ /V₁
T₂ = 1.00 ×10²L × 275 K / 32.0 L
T₂ = 27500 L.K / 32.0 L
T₂ = 859.4 K
Answer: Option (C) is the correct answer.
Explanation:
A neutral hydrogen atom is defined as the atom in which electrons are resent in their ground state only.
Basically in a neutral atom electrons are present in their parent shell.
For example, atomic number of hydrogen is 1 and electronic configuration of a neutral atom of hydrogen is 
.
Hence, it means there is only one electron present in its valence shell. So, in order to attain stability it will readily react with another atom to gain or share an electron.
Thus, we can conclude that the statement it is less chemically reactive than an atom of aluminum (Al), is false.
Answer:
banging rocks together to see which make make a spark and create fire painting pictures is an example of art and sleeping in caves is survival
