Answer:
True
Explanation:
Here is an example: chemical properties include flammability, toxicity, acidity, reactivity. we observe the changes of these properties. Therefore, It's true.
Answer:
He is wrong . Most accurate is Buret .
Explanation:
The number of significant figure denotes the level of accuracy of a measurement .
Beaker can measure liquid in mL upto significant figure of 2 . That means it can measure volume in terms of 10 , 20 , 30mL etc . It can not measure 25 mL
accurately . The last figure of 28 mL is read by guess in the question . So it is not an accurate measurement .
Similarly , graduated cylinder can measure liquid upto significant figure of 3 . That means it can measure volume in terms of 11 , 22 , 33 mL etc . It can not measure 25.5 mL accurately . The last figure of 28.3 mL is read by guess in the question . So it is less accurate measurement .
Similarly , buret can measure liquid upto significant figure of 4 . That means it can measure volume in terms of 11.2 , 22.3 , 33.5 mL etc . It can not measure 25.53 mL accurately . The last figure of 28.32 mL is read by guess in the question . So it is most accurate among all the three instrument because it can measure accurately mL upto one tenth of it .
It starts with a cation and ends with a nonmetal anion. To recap, cations are your positively charged elements and anions are negatively change and usually with the ending “ide”. For example, potassium a metal and chlorine a nonmetal (KCl) would form the word potassium chloride.
Answer:
127529 KJ
Explanation:
Since 1gallon = 3.78 L= 3780 ml
The density of C8H18= 0.703 g/mL
Density = mass/volume
Mass= Density × volume
Mass= 0.703 g/mL × 3780 ml
Mass= 2657.34 g
Molar mass of C8H18= 114 g/mol
Number of moles= mass/molar mass
Number of moles= 2657.34/114
Number of moles= 23.31 moles
Since 1 mole evolved=5471 kJ
23.31 moles = 5471 kJ × 23.31 = 127529 KJ
