Enable contrast version

# Tutor profile: Yikun L.

Inactive
Yikun L.
Volunteer tutor for 2 years
Tutor Satisfaction Guarantee

## Questions

### Subject:Pre-Algebra

TutorMe
Question:

Use the following function rule to find f(16). f(x) = x^0.5+8

Inactive
Yikun L.

f(16)=16^0.5+8=12

### Subject:Basic Math

TutorMe
Question:

In a sack of 50 marbles, there are 20 more red marbles than blue marbles. All of the marbles in the sack are either red or blue. How many blue marbles are in the sack?

Inactive
Yikun L.

Assume there are x blue marbles, then the number of red marbles is x+20. There are 50 marbles in total, so x+x+20=50. x=15, which means there are 15 blue marbles x+20=35, which means there are 35 red marbles.

### Subject:Basic Chemistry

TutorMe
Question:

Ethyl acetate, an undesirable side-product formed during the fermentation step of beer brewing, contains 54.53% C, 9.15% H, and 36.32% O by mass. Its molar mass is 88.1 g/mol. a) What is the empirical formula of ethyl acetate? b) What s the molecular formula of ethyl acetate?

Inactive
Yikun L.

a) Assume the sample of ethyl acetate has a mass of 100g. C H O Mass/g 54.53 9.15 36.32 Molar mass/ g/mol 12.01 1.008 16.00 # of moles 4.540 9.08 2.27 net ratio of moles 2 4 1 C:H:O=2:4:1, so the empirical formula of ethyl acetate is C2H4O. b) The first step is to calculate the molar mass of ethyl acetate. Mr(C2H4O)=12.01*2+1.008*4+16.00*1=44.05g/mol 88.01/44.05=2 so the molecular formula is C4H8O2.

## Contact tutor

Send a message explaining your
needs and Yikun will reply soon.
Contact Yikun

Start Lesson

## FAQs

What is a lesson?
A lesson is virtual lesson space on our platform where you and a tutor can communicate. You'll have the option to communicate using video/audio as well as text chat. You can also upload documents, edit papers in real time and use our cutting-edge virtual whiteboard.
How do I begin a lesson?
If the tutor is currently online, you can click the "Start Lesson" button above. If they are offline, you can always send them a message to schedule a lesson.
Who are TutorMe tutors?
Many of our tutors are current college students or recent graduates of top-tier universities like MIT, Harvard and USC. TutorMe has thousands of top-quality tutors available to work with you.
BEST IN CLASS SINCE 2015
TutorMe homepage