This assignment 10 points and is due before the Basic Knowledge Quiz of our next
ID: 701494 • Letter: T
Question
This assignment 10 points and is due before the Basic Knowledge Quiz of our next·lecture. is worth session. No LATE assignments are accepted without be shown and the answer reported with correct sig figs and units to earn full credit prfor approval. For calculation questions, the complete setup must Circle the BEST answer for questions 1 through 3 How do phase changes differ from chemical reactions A) Phase changes occur more rapidly than chemical reactions 1. do not involve breaking or making covalent bonds C) Only chemical reactions follow the conservation of matter D) There is no difference between them E) Only chemical reactions involve changes in energy 2. Which statement best describes why steam burns are more severe than boling water burns A) Steam covers the skin more thoroughly than water B) Steam transfers more heat energy to the skin than boiling water due to the change of state from gas to liquid C) Steam remains hot in the air while water cools quickly as it pours. D) Actually, steam does not cause more severe burns than boling water. E) Steam is hotter than boiling water 3. Which statement best describes why it is important to know the vapor pressure of a material before working with it? A) It is not important to know the vapor pressure of materials. B) It is important because the toxicity increases for materials with high vapor pressure. C) It is important because the risk of inhalation increases for materials with high vapor pressure. D) It is important because the risk of inhalation Increases for materials with low vapor pressure. E It is important because the toxicity increases for materials with low vapor pressure. 4. Which molecule in this table has the highest boling point Acetone Methanol Formic acid hloro- Pentane Name 39 61 Vapor ressure torr) at 20 C 5. A gas sample occupies 4.2 Lat 650 tor. What is the volume of this gas at 2.5 atmExplanation / Answer
Ans 1
Phase change in any substance, chemical reactions are not required.
Phase change is a physical phenomenon, the bonding of a substance remains same. It doesn't change.
While in chemical reaction, the formation of new molecules take place by breaking or making bonds.
Option B is the correct answer
Ans 2
Steam has more energy than boiling water. The transfer of heat from steam to body is more rapid than that of boiling water.
Due to higher heat content and higher rate of heat transfer steam burns are more severe.
Option B is the correct answer
Ans 3
It is important to know the vapor pressure
For low vapor pressure, boiling point of the substance is higher.
For high vapor pressure, boiling point of the substance is lower.
For high vapor pressure, there are chances of boiling and risk of inhalation increases.
Option C is the correct answer