Answer:
Infrared thermography
Explanation:
Infrared thermography is equipment or method, which detects infrared energy emitted from object, converts it to temperature, and displays image of temperature distribution. ... We call our equipment as infrared thermography considering such generalization of the terminology.
D will because water just turns from liquid to a gas by adding heat. That is a physical change. The other equations are chemical changes.
Answer:
Experiments to determine mechanisms involve looking at indirect evidence to help support or disprove a proposed mechanism.
Most intermediates are not typically isolated to determine reaction mechanisms.
Carbocations are very reactive and are typically not isolated for analysis.
Scientists can prove that a specific mechanism exists.
Evidence of intermediates sometimes can be seen using techniques such as nuclear magnetic resonance spectroscopy
Explanation:
The study of reaction mechanism and chemical kinetics often form the main thrust of study in organic, inorganic and physical chemistry.
We often want to know the actual processes involved in the conversion of one specie to another. Unfortunately, this information may have to be obtained indirectly by certain chemical reactions or by the use of new instrumental methods such as nuclear magnetic resonance spectroscopy.
Many organic reactions have carbocation intermediates. These carbocations are relatively short-lived and are transient intermediates which are rarely isolated unless they are isolated in a molecular cage using a macromolecule or in superacids.
By intensive study, scientists can proof or disprove the authenticity of any proposed mechanism.
We must know that a transition state has partial bonds. It is often an extremely short-lived specie which cannot be isolated.
Answer:
400 mL
Explanation:
Given data:
Mass of barium = 2.17 g
Pressure = 748 mmHg (748/760 = 0.98 atm)
Temperature = 21 °C ( 273+ 21 = 294k)
Milliliters of H₂ evolved = ?
Solution:
chemical equation:
Ba + 2H₂O → Ba(OH)₂ + H₂
Number of moles of barium:
Number of moles = mass/ molar mass
Number of moles = 2.17 g / 137.327 g/mol
Number of moles = 0.016 mol
Now we will compare the moles of barium with H₂.
Ba : H₂
1 : 1
0.016 : 0.016
Milliliters of H₂:
PV = nRT
V = nRT/P
V = 0.016 mol × 0.0821 atm. mol⁻¹.k⁻¹.L×294 k/0.98 atm
V = 0.39 atm. L/0.98 atm
V = 0.4 L
L to mL
0.4 × 1000 = 400 mL
Answer:
The volume is 1.2L
Explanation:
Initial volume (V1) = 700mL = 0.7L
Initial temperature (T1) = 7°C = (7 + 273.15)K = 280.15K
Initial pressure = 106.6kPa = 106600Pa
Final temperature (T2) = 27°C = (27 + 273.15)K = 300.15K
Final pressure (P2) = 66.6kPa = 66600Pa
Final volume (V2) = ?
To solve this question, we need to use combined gas equation which is a combination of Boyle's law, Charles Law and pressure law.
(P1 × V1) / T1 = (P2 × V2) / T2
solve for V2 by making it the subject of formula,
P1 × V1 × T2 = P2 × V2 × T1
V2 = (P1 × V1 × T2) / (P2 × T1)
V2 = (106600 × 0.7 × 300.15) / (66600 × 280.15)
V2 = 22397193 / 18657990
V2 = 1.2L
The final volume of the gas is 1.2L
