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
ArbitrLikvidat [17]
3 years ago
7

Which of the following is true about elements?

Chemistry
1 answer:
kondor19780726 [428]3 years ago
6 0

Answer:

The first one

Explanation:

Elements are as simple as it gets

You might be interested in
Which ones are wrong please tell the right answer it Hlep me a lot
DiKsa [7]
13.) would be cytoskeleton and number 16.) would be lysosomes
6 0
3 years ago
Write a chemical equation for the reaction that occurs in the following cell: Cu|Cu2+(aq)||Ag+(aq)|Ag Express your answer as a b
Alinara [238K]

Answer:

Explanation:

The cell reaction properly written is shown below:

              Cu|Cu²⁺_{aq} || Ag⁺_{aq} | Ag

From this cell reaction, to get the net ionic equation, we have to split the reaction into their proper oxidation and reduction halves. This way, we can know that is happening at the electrodes and derive the overall net equation.

  Oxidation half:

                  Cu_{s}  ⇄ Cu²⁺_{aq} + 2e⁻

At the anode, oxidation occurs.

  Reduction half:

                  Ag⁺_{aq} + 2e⁻ ⇄ Ag_{s}

At the cathode, reduction occurs.

To derive the overall reaction, we must balance the atoms and charges:

             Cu_{s}  ⇄ Cu²⁺_{aq} + 2e⁻

              Ag⁺_{aq} + e⁻ ⇄ Ag_{s}

  we multiply the second reaction by 2 to balance up:

         2Ag⁺_{aq} + 2e⁻ ⇄ 2Ag_{s}

The net reaction equation:

Cu_{s} + 2Ag⁺_{aq} + 2e⁻⇄ Cu²⁺_{aq} + 2e⁻ + 2Ag_{s}

We then cancel out the electrons from both sides since they appear on both the reactant and product side:

  Cu_{s} + 2Ag⁺_{aq} ⇄ Cu²⁺_{aq} + 2Ag_{s}

6 0
3 years ago
Which sample contains a total of 3.0 x 10^23 molecules?
belka [17]
Given that 1 mole contains 6.02x10^23 molecules, 3.0x10^23 is just around half a mole. Then we check the number of moles for each choice:

A. This is approximately half a mole, since the molar mass of Br2 is 159.8 g/mol.
B. He has a molar mass around 4 g/mol, so this is 1 mole.
C. H2 has a molar mass of 2.02 g/mol, so this is 2 moles.
D. Li has a molar mass of around 6.97 g/mol, so this is around 2 moles.

Therefore the only choice that fits is A. 80 g of Br2.
3 0
3 years ago
Explain with the help of examples difference between elements and compounds​
djyliett [7]

Answer:

Elements are pure substances which are composed of only one type of atom. Compound are substances which are formed by two or more different types of elements that are united chemically in fixed proportions. ... Some of the examples of elements are Iron, Copper, Gold, etc. A few examples of compounds are NaOH, NaCl, etc.

5 0
3 years ago
A helium-filled balloon has a volume of 2.48 L and a pressure of 150 kPa. The volume of the balloon increases to 2.98 L after yo
Tema [17]

Answer:

THE NEW PRESSURE OF THE HELIUM GAS AT 2.98 L VOLUME IS 124.8 kPa.

AT AN INCREASE ALTITUDE, THERE IS A LOWER PRESSURE ENVIRONMENT AND THE HELIUM GAS PRESSURE DECREASES AND HENCE AN INCREASE IN VOLUME.

Explanation:

The question above follows Boyle's law of the gas law as the temperature is kept constant.

Boyle's law states that the pressure of a fixed mass of gas is inversely proportional to the volume, provided the temperature remains constant.

Mathematically, P1 V1 = P2 V2

P1 = 150 kPa = 150 *10^3 Pa

V1 = 2.48 L

V2 = 2.98 L

P2 = ?

Rearranging the equation, we obtain;

P2 = P1 V1 / V2

P2 = 150 kPa * 2.48 / 2.98

P2 = 372 *10 ^3 / 2.98

P2 = 124.8 kPa.

The new pressure of the gas when at a height which increases the volume of the helium gas to 2.98 L is 124.8 kPa.

6 0
3 years ago
Other questions:
  • The normal freezing point of a certain liquid
    9·1 answer
  • Carbon is important to the structure of macromolecules because it has a valence of 4. what does this mean?
    9·1 answer
  • In an energy diagram, the reactants are at a higher potential energy compared to the products. Which of the following best descr
    15·1 answer
  • Which best compares freezing and condensation?
    9·1 answer
  • Which of these reactions can be classified as synthesis reactions?
    6·1 answer
  • What does the p mean in 1s22s22p63s??
    14·1 answer
  • Write a chemical equation for nh4+(aq) showing how it is an acid or a base according to the arrhenius definition.
    8·2 answers
  • What do acids react with in limestone to form giant cave systems?
    15·2 answers
  • How moles are in 45.7g of CH3?
    10·1 answer
  • Student added a strip of aluminium metal in aqueous copper(2)Sulfate but no reaction occured. Suggest a reason why.
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!