Ai ơi giúp mình 3 câu này với. 1. Từ CH4 và các chất vô cơ cần thiết khác hãy điều chế cao su isopren 2. Sắp xếp các chất sau theo chiều acid, base tăng dần, giải thích a, 4-clophenol; 2,4-diclophenol; 2,4,6-triclophenol b, HCOOH, CH3COOH, (CH3)2CH-COOH, C6H5COOH 3. C6H6 (xúc tác H2SO4)=>A(xúc tác Br2)=>B(xúc tác H2O, nhiệt độ,p)=>C(xúc tác NaOH, 300 độ, 200atm)=>D

The element that has the greatest electronegativity is

1. an experiment in your science class lists the materials needed for the lab. it is your job, as a lab partner, to measure out 25 ml of distilled water and 2.5 grams of magnesium. what lab measuring tools would you choose to measure each substance and how would you use each tool to get the correct amounts? be sure to describe the process you would follow step-by-step. (5 points) 2.which of the following is an si base unit for measuring mass? (2 points) ampere gram meter pound 3.which of the following is an si base unit for time? (2 points) decades hours minutes seconds 4.which of the following tools should a scientist use to measure an object in milligrams? (2 points) graduated cylinder pan balance tape measure thermometer 4.which of the following tools should a scientist use to measure an object in milligrams? (2 points) graduated cylinder pan balance tape measure thermometer. 5.a pencil beside a metric ruler. the ruler is scaled from 1 centimeter to 10 centimeters, with markings for millimeters between each number. one end of the pencil is beside the 0 on the ruler, and the pencil point is beside the 5. which of the following measurements is accurate but not precise? (2 points) 5 mm 5 cm 50 mm 50 cm 6. which of the following prefixes represents the largest value? (2 points) giga hector kilo milli 7. which of the following types of graphs is best for plotting the percentages of a whole value in a data set? (2 points) bar graph circle graph histogram line graph

What is the magnitude of the force of gravity between to 1000 kg cars which are separated by distance of 25. 0 km on an interstate highway? the force between the two cars will be what