1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
denis23 [38]
3 years ago
9

Does anyone know the answers for these

Chemistry
1 answer:
Alexeev081 [22]3 years ago
4 0

Answer: 1. 0.045moles

2.  2.10 grams

Explanation:

According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number 6.023\times 10^{23} of particles.

To calculate the moles, we use the equation:

\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}

1. \text{Number of moles of zinc nitrate}=\frac{8.51g}{189.36g/mol}=0.045moles

2. Mass of C_2H_4=moles\times {\text {Molar mass}}=0.075moles\times 28.05g/mol=2.10g

You might be interested in
1. Gases are made up of molecules which are relatively far apart.
bulgar [2K]
The answer is A) 1...
6 0
3 years ago
You are instructed to create 900. mL of a 0.29 M phosphate buffer with a pH of 7.8. You have phosphoric acid and the sodium salt
Aleksandr [31]

Answer:

B and C

Explanation:

When we have to do a buffer solution we always have to choose the reaction that has the <u>pKa closer to the desired pH value</u>. When we find the pKa values we will obtain:

pKa_1=-Log[6.9x10^-^3]=2.16

pKa_2=-Log[6.2x10^-^8]=7.20

pKa_3=-Log[4.8x10^-^13]=12.31

The closer value is pKa2 with a value of 7.2. Therefore we have to use the second reaction. In which  H_2PO_4^-^1 is the <u>acid</u> and HPO_4^-^2 is the <u>base</u>. Therefore the answer for the first question is B and the answer for the second question is C.

8 0
3 years ago
100 POINTS PLEASE HELP!!! ASAP!!!! CORRECT ANSWER GETS BRAINLIEST
aalyn [17]

If a substance has a relatively low melting point (below 400ºF), then it is either molecular polar or molecular non-polar

If a substance has a high melting point, then it is either metallic, covalent network, or ionic

The stronger a substance’s bonds, the higher its melting point

4 0
3 years ago
By what process do electromagnetic waves release from the materials they contact?
Rudik [331]

Answer:

The photoelectric effect

Explanation:  hope it helps

5 0
3 years ago
A student is worried about determining if a chemical is radioactive. Which
Mamont248 [21]

Answer:

Hazards Identification

Explanation:

A safety data sheet, SDS, is an informational document provided by the manufacturer or importer of a hazardous chemical detailing the chemical, physical, health, and environmental health hazards associated with the chemical as well as safety precautions in handling the chemical.

Some of the sections in the SDS include:

Product Information: It identifies the chemical as well as its recommended uses. The contact information of the manufacturer is also provided.

Fire fighting methods: It gives measures and guidelines necessary for fighting a fire caused by the chemical.

Physical and chemical properties: states the physical and chemical properties of the chemical substance such as:  appearance, odor, pH, melting/freezing point, boiling point and boiling range, flammability, etc.

Hazards identification: states the hazards of the chemical and the necessary warnings regarding the hazards. Some of the information provided include: hazard classification of the chemical (for example flammable liquid, oxidizing gases,explosives, etc), signal word, hazard statement (for example radioactive), pictograms, precautionary statements, etc.

<em>From the above information provided, the student should refer to the hazards identification section.</em>

8 0
3 years ago
Other questions:
  • What is the answer, with the correct number of decimal places, for this problem? 4.392 g+ 102.40 g + 2.51 g=
    12·1 answer
  • When magnesium reacts with chlorine, magnesium ions, Mg2+, and chloride ions, Cl−are formed. In this reaction, magnesium atoms A
    7·1 answer
  • When paper is burned, the mass of the remaining ash is less than the mass of the original paper.
    6·1 answer
  • 50 points please do this In your OWN WORDS DO NOT COPY FROM SOMEWHERE ELSE!
    6·1 answer
  • How does an object become negatively charged?
    9·2 answers
  • Which of the following elements would have the greatest attraction for
    10·1 answer
  • Explain how convection transfers heat. Use information from this video above. Make sure you include the words: heat, density, co
    6·2 answers
  • Can someone Help pls :)
    6·1 answer
  • What is the 3 planet
    8·2 answers
  • WILL GIVE BRAINIEST ANSWER A chemical equation has different numbers of atoms on the left and right sides.
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!