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
sergij07 [2.7K]
4 years ago
14

Which statement best describes elements ?

Chemistry
1 answer:
umka2103 [35]4 years ago
6 0
B is the right one. They aren't compounds, which is a mix of two elements. 
You might be interested in
When 5.00 g of NH4NO3 is dissolved in 100.0 g of water in a styrofoam cup, the T = - 3.82 ^°C. Is the process of dissolving ammo
miv72 [106K]

Answer:

The process is endothermic.

Heat is 26,9 kJ/mol

Explanation:

The dissolution of NH₄NO₃ in water is:

NH₄NO₃ → NH₄⁺ + NO₃⁻

As the change of temperature in the cup is ΔT = -3,82°C

<em>The process is endothermic</em>. Because the temperature is decreasing in the process. That means the process needs heat.

Assuming the  heat capacity of the solution is 4.18 J/Kg :

q = -C×m×ΔT

Where q is heat, C is heat capacity (4,18J/Kg), m is mass (105g) and ΔT is change in temperature (-3,82°C)

q = 1677 J ≈ <em><u>1,68kJ</u></em>

The moles of NH₄NO₃ dissolved are:

5,00g × (1mol / 80,043g) = <em><u>0,0625 moles</u></em>

That means heat of this process in kJ/ mol is:

1,68kJ / 0,0625moles = <em>26,9 kJ/mol</em>

<em />

I hope it helps!

8 0
3 years ago
Chemical energy is<br> energy that is
Flauer [41]
Stored in bonds of chemical compounds is the right answer
4 0
3 years ago
Read 2 more answers
Addison wants to create a new type of skin cream that will help teenagers with their acne. She should study _____.
kipiarov [429]
I think it’s chemistry .. I don’t know I might be wrong ;-; ...
8 0
4 years ago
Read 2 more answers
Natural substances that have characteristic properties and somewhat specific chemical compositions are called ______.
Darya [45]

Answer:

Minerals

Explanation:

Minerals are usually defined as naturally occurring inorganic substances, that are comprised of specific chemical composition as well as having a well organized internal structure of atoms.

Different mineral forms under different conditions and under different geological settings. These minerals combine with one another giving rise to the formation of rocks.

They are characterized by the presence of both physical as well as chemical properties.

Example of some minerals includes, Calcite, Fluorite, Quartz, and Feldspar.

8 0
3 years ago
Part 1: name two elements that have the same properties as sodium (na). (4 points) part 2: determine the number of protons, elec
Maslowich

  • Part 1: Two elements with the same properties as Sodium(Na) are Lithium(Li) and Potassium(K).
  • Part 2: Calcium(Ca) has 20 protons, 20 electrons and 20 neutrons.

  • Elements that have the same properties ( physical and chemical ) are usually found on the same group. A group ( also called family ) in chemistry, means a column or a vertical line of elements in the periodic table of elements. Elements in the same group are similar because they have the same number of electrons in their outermost shell. The two most common elements found in the same group as Sodium(Na) are Lithium(Li) and Potassium(K). All three elements are in Group 1, have 1 electron in their outermost shell and are highly electropositive.

  • The number of protons in any atom is always equal to the atomic number of that element, usually denoted by the letter Z. From the periodic table of elements, The atomic number of Calcium(Ca) is 20, so the number of protons will be 20. The number of electrons in any given atom is also equal to the number of protons in that atom, therefore the number of electrons in Calcium(Ca) is also 20. To find the number of neutrons, subtract the number of protons from the atomic mass as;                                                                       Atomic mass = Number of protons + Number of neutrons         Calcium(Ca) has an atomic mass of 40, so it's number of neutrons will be;                                                                                                         40 - 20 = 20 neutrons                                                                   Hence, Calcium(Ca) has 20 protons, 20 electrons, and 20     neutrons.

To know more about elements and the periodic table, go to;

brainly.com/question/14347616    

#SPJ4  

                                       

5 0
2 years ago
Other questions:
  • What are dependent variables?
    5·2 answers
  • 10 grams of sodium hydroxide, NaOH, is dissolved in 0.25 liters of solution. Determine the molarity (M).
    7·1 answer
  • What type of bond occurs between atoms having nearly equal attraction for the electrons?
    11·1 answer
  • Please help me with this every time I ask a question on Brainly I never get an answer please.
    5·1 answer
  • What is the approximate mass of a 100-N person on Earth? Question options: 1 kg 10 kg 100 kg 1,000 kg
    8·1 answer
  • What is the hydronium (H3O+) concentration of a solution with a pH of 3.60? A. 2.5 × 10-4 M B. 3.0 × 10-4 M C. 4.0 × 10-11 M D.
    8·2 answers
  • A. Balance the following equation:
    5·1 answer
  • PLS HELP MARKING BRAINLIEST! (Dont answer if u dont know and please don't answer random things-)
    12·2 answers
  • Need help on both questions. Only if you know.
    5·1 answer
  • How many grams are there in 9.4 x 1025 molecules of H2?
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!