subject
Chemistry, 02.09.2020 06:01 shyra94

Round the following numbers to the number of significant figures indicated: 345 (2 s. f.)
7850 (1 s. f.)
24.68 (3 s. f)
8.005 (3 s. f)
0.005758 (3 s. f)
1.25x1012 (2 s. f)

ansver
Answers: 1

Another question on Chemistry

question
Chemistry, 21.06.2019 23:00
Write a brief passage describing a neutral atom of nitrogen-14 (n-14). describe the number of protons, neutrons, and electrons in the atom, where each type of particle is located, and how the terms atomic number, mass number, and atomic mass are related to the particles. use the periodic table to you. 14 protons and eletrons since its a neutral atom
Answers: 1
question
Chemistry, 22.06.2019 05:20
Why does the sun appear to be the brightest star in the sky? a- its apparent brightness is much greater than other stars. b- it burns more gas, making it brighter than any other star. c- it is the largest star in the galaxy, so it is the brightest star. d- its relative distance to earth is closer than the other stars.
Answers: 1
question
Chemistry, 22.06.2019 08:00
Straightforward questions answered in the powerpoint slidesreaction: heating the starting materials under refluxwhat does it mean to heat under reflux? why do we choose water as the reflux solvent? what are boiling chips used for? why do we put a condenser on top of the reaction? why do we add heat and let the reaction stir for 30 minutes? why do we add sulfuric acid to the reaction after it cools as opposed to when it’s still hot? separation: filtration of precipitatewhy don’t we do an aqueous and organic extraction in the separatory funnel? why do you rinse the salicylic acid on the filter with ice cold water? purification: recrystallization of salicylic acid (no hot filtration needed)what is the difference in the amount of room temperature water vs. boiling water needed to dissolve the salicylic acid (assume a 1.2 gram yield of salicylic acid)? remember, in the lab if you need x ml of boiling water to dissolve a solid, then you should add a little more (definitely no more than 1.5 times the theoretical amount) to ensure it doesn’t recrystallize prematurely.analysis: melting point of salicylic acidwhat can you conclude if the melting point of the salicylic acid you just synthesized is 152-155oc and the 1: 1 mix of your product and “synthetic” salicylic acid is 151-154oc?
Answers: 1
question
Chemistry, 22.06.2019 11:00
What is the molar mass of a gas that has density of 2.054 g/l
Answers: 2
You know the right answer?
Round the following numbers to the number of significant figures indicated: 345 (2 s. f.)
78...
Questions
question
Mathematics, 08.07.2019 14:50