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
IRINA_888 [86]
3 years ago
8

Which parts (postulates) of Dalton's atomic theory has been modified in light of later discoveries

Chemistry
1 answer:
professor190 [17]3 years ago
8 0

Explanation:

1) Atoms can not be subdivided. It has been changed as it is possible to divide an atom into Protons, Neutrons and Electrons as well as other smaller particles.

2) The regulations for the chemical mixture have always been altered to the rules for the chemical combination in the creation of organic compounds may be denied.

3)Atoms are of a particular element are identical in all respects i. e. they have same mass and similar properties.

It was modified. And according. to new search;

Atoms of the same element may not be always identical.

You might be interested in
Populations of __________ live in the human large intestine. These beneficial organisms help make certain vitamins and digest po
stira [4]
The answer is A) Bacteria
6 0
3 years ago
Read 2 more answers
What is the difference between a pure solvent and a solution? Do they have the same physical properties?
pychu [463]

Answer:

The physical properties of a solution are different from those of the pure solvent. ... Colligative properties are those physical properties of solutions of nonvolatile solutes that depend only on the number of particles present in a given amount of solution, not on the nature of those particles.

5 0
2 years ago
What substance is neither an acid nor a base? How does it stay neutral? HURRY PLS
andreyandreev [35.5K]

Answer:

21. Most metals are brittle.

22. increases from top to bottom within the group

23. Neon is the most stable element because its highest occupied energy level is filled.

24. transfer of electrons

25. electrons are not shared equally between atoms

26. BeCl2

27. double-replacement and decomposition

28. exothermic

29. The reaction rate decreases.

30. The salt dissolved most quickly in the warm water.

31. saturated

32. feels slippery

33. hydroxide ions in solution

34. stay about the same

35-40. I do not know.

41. a bee hovering around a bee hive

42. the number of valence electrons in atoms of the element

Explanation:

21. Metals are ductile and malleable (conveniently also characteristics for chewing gum). They are stretchy and squishy. Brittle is the opposite of stretchy and squishy, and is a characteristic of non-metals.

22. On the periodic table, elements higher up are safer to use in labs. They are safer because they are less likely to react with other substances. Therefore the tendency to react with other substances increases from top to bottom within the group.

23. "Noble gases stable" (periodic table song by ASAP Science). Neon is a noble gas, therefore it is stable. When elements have only one electron to gain or lose, they are very reactive or least stable.

24. The formation of an ionic bond (metal + non-metal) is caused by the giving and receiving of electrons. Neutrons and protons do not transfer. Electrons are shared in covalent/molecular bonds (between non-metals).

25. A polar covalent bond occurs between non-metals, therefore they share electrons (ionic bonds transfer electrons). Non-metals become anions (whereas metals become cations). Polar bonds have unequal sharing and nonpolar bonds have equal sharing.

26. A one-to-two ratio of  beryllium ions to chloride ions means for every Be, there are two Cl. The number of atoms is represented by the ratio, and the numbers of atoms are written as subscripts after the element symbol.

27. MgCO2  reacting with HNO3  to form magnesium nitrate and carbonic acid is a double-replacement reaction. The elements in the beginning substances "switch partners" to form the products.

Carbonic acid then breaks down into water and carbon dioxide is decomposition. This occurs when the elements that make up a compound are split up.

28. In 2Cu + O2  => 2CuO + 315 kJ , the energy is on the right side. The right side is the products, or the stuff that was made. kJ is a unit to measure energy, therefore energy was made. Exothermic is the term that means energy was released.

29. Since oxygen is needed for a fire to burn, decreasing the oxygen slows the reaction rate (the reaction is burning, formally known as combustion).

30. Two things help substances dissolve: heat and stirring. Warm water is hotter than room-temperature water and ice water. This makes the salt dissolve faster.

31. A solution that contains more solute than it would normally hold is saturated. Saturated means there is a more than concentrated amount of solute in the solution. Concentrated is when there is a maximum amount of solute that will dissolve.

32. Acids do not feel slippery -- that is a characteristic of a base. To remember, bases are generally soaps and soaps are slippery. Acids taste sour  and bases taste bitter. Both acids and bases change the color of an indicator .

33. A base produces hydroxide ions, represented by OH. The OH is usually at the end of the chemical formula. Acids produce hydrogen ions, generally written at the front of the chemical formula.

34. Adding a little bit of acid to a buffer will cause the pH of the solution to stay about the same, probably increase a little. Buffer solutions are meant to make the pH "buffer". To remember, DVDs used to buffer. It's the same thing as "lag" for phones.

35-40: I'm sorry, I have no answer.

41. Electrons orbit like the plants revolve around the sun. Electrons revolve around a nucleus. A bee hovering around a bee hive  is probably flying around it in circles.

42. The tendency of an element to react is closely related to the number of valence electrons in atoms of the element.  If the valency is 8, the electron shell is full. The element is stable, opposite to reactive -- this applies to all noble gases (group 8A on the periodic table). If the valency is 1 or 7, the element is very close to being stable but not, the "desire" is so great and makes the element very reactive.

4 0
3 years ago
Read 2 more answers
Cholesterol is an example of a(n) _____. <br> monosaccharide polysaccharide <br> lipid <br> enzyme
seropon [69]

Cholesterol is an example of a lipid.

8 0
3 years ago
What is the molarity of a solution that contains 1000.0 mg of AgNO3 that has been dissolved in 500 mL of water
Vaselesa [24]

0.012moldm⁻³

Explanation:

Given parameters:

Mass of AgNO₃  = 1000mg

Volume of water = 500mL

Unknown:

Molarity of solution  = ?

Solution:

The molarity of a solution is the number of moles of a solute dissolved in volume of solvent.

 Molarity = \frac{xnumber of moles}{Volume}

 

Number of moles of AgNO₃  = ?

   Number of moles = \frac{mass}{molar mass}

Molar mass of AgNO₃ = 108 + 14 + 3(16) = 170g/mol

   convert mass to g;

      1000mg = 1g

 Number of moles  = \frac{1}{170}  = 0.00588moles

   convert the given volume to dm³;

       1000mL  = 1dm³;

        500mL = 0.5dm³

Now solve;

  Molarity = \frac{0.00588}{0.5}  = 0.012moldm⁻³

learn more:

Molarity brainly.com/question/9324116

#learnwithBrainly

4 0
3 years ago
Other questions:
  • Sprinters set in the starting blocks at the beginning of a race rely on what kind of energy conversion?
    12·1 answer
  • Using the following thermochemical data, what is the change in enthalpy for the following reaction?
    14·1 answer
  • As a liquid boils at its normal boiling point, it's temperature..1) remains the same2) increases 3) decreases
    15·1 answer
  • Al2(CrO4)3 percentage of Al
    13·1 answer
  • Fill in the blank with the correct number to balance the equation: 4Cr + 3O2 → ___Cr2O3. (Enter only a whole number.)
    12·2 answers
  • What type of atoms will end up with a negative charge?
    6·2 answers
  • The igneous rock texture that is characterized by two distinctly different crystal sizes is called ____.
    8·2 answers
  • A 0.3423 g sample of pentane, C5H12, was burned in a bomb calorimeter. The temperature of the calorimeter and the 1.000kg of wat
    7·1 answer
  • Emission results in the release of energy without any apparent change in mass or nuclear charge.
    6·1 answer
  • *WILL GIVE BRAINLIEST FOR CORRECT ANSWER*<br> question in picture
    15·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!