Polyesters and polyamides are types of synthetic polymer. Which statements are correct? 1. They are made by addition polymerisation. 2. They are made by condensation polymerisation. 3. The monomers from which they are made are unsaturated hydrocarbons. 4. The monomers from which they are made contain reactive functional groups at their ends A. 1 and 3 B.1 and 4 0.2 and 3 D.2 and 4

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? a. the balloons both rise. the cold balloon is larger than the warm balloon. b. the balloons rise at the same rate. both balloons are the same size. c. the warm balloon expands and rises. the cold balloon shrinks and sinks. d. the cold balloon expands and rises. the warm balloon shrinks and sinks.

How many atoms of mg are present in 97.22 grams of mg? 6.022 × 1023 2.408 × 1024 4.818 × 1024 5.855 × 1025

What is the main purpose of patent attorneys? defend the company against legal claims manage financial investments invent new products protect rights to new products and processes