Molarity prctice c.10.c

Why aren’t subatomic particles, which are smaller than an atom, considered to be the building blocks of matter?

Elena L [17]

Concrete is formed of sand. Is it incorrect to suggest that some houses are built using concrete blocks?

8 0

3 years ago

A change in state is a physical change.<br><br>True or false

Morgarella [4.7K]

Answer: Depending on the state of change it can be a physical change. Example: Evaporation is the physical change of a liquid turned into a gas.

That said, I'm pretty sure the answer is (True)

Note: Hope this is correct and it helps. Good luck :)

5 0

3 years ago

What happens to the cell membrane during exocytosis?

Cloud [144]

Answer:

Endocytosis and Exocytosis: Differences and Similarities

ARTICLE Apr 28, 2020

by Nicole Gleichmann

Endocytosis and Exocytosis: Differences and Similarities

Endocytosis and exocytosis are the processes by which cells move materials into or out of the cell that are too large to directly pass through the lipid bilayer of the cell membrane. Large molecules, microorganisms and waste products are some of the substances moved through the cell membrane via exocytosis and endocytosis.

Why is bulk transport important for cells?

Cell membranes are semi-permeable, meaning they allow certain small molecules and ions to passively diffuse through them. Other small molecules are able to make their way into or out of the cell through carrier proteins or channels.

But there are materials that are too large to pass through the cell membrane using these methods. There are times when a cell will need to engulf a bacterium or release a hormone. It is during these instances that bulk transport mechanisms are needed.

Endocytosis and exocytosis are the bulk transport mechanisms used in eukaryotes. As these transport processes require energy, they are known as active transport processes.

Vesicle function in endocytosis and exocytosis

During bulk transport, larger substances or large packages of small molecules are transported through the cell membrane, also known as the plasma membrane, by way of vesicles – think of vesicles as little membrane sacs that can fuse with the cell membrane.

Cell membranes are comprised of a lipid bilayer. The walls of vesicles are also made up of a lipid bilayer, which is why they are capable of fusing with the cell membrane. This fusion between vesicles and the plasma membrane facilitates bulk transport both into and out of the cell.

What is endocytosis? Endocytosis definition and purposes

Endocytosis is the process by which cells take in substances from outside of the cell by engulfing them in a vesicle. These can include things like nutrients to support the cell or pathogens that immune cells engulf and destroy.

Endocytosis occurs when a portion of the cell membrane folds in on itself, encircling extracellular fluid and various molecules or microorganisms. The resulting vesicle breaks off and is transported within the cell.

8 0

3 years ago

What describes Rutherford’s model of the atom?

HACTEHA [7]

Rutherford's model shows that an atom is mostly empty space, with electrons orbiting a fixed, positively charged nucleus in set, predictable paths. ... It was after this that Rutherford began developing his model of the atom.

8 0

4 years ago

In the reaction MnO₂ + 4HCI MnCl₂ + 2H₂O + Cl₂, which<br> species is reduced?

Triss [41]

Answer:

4 HCl (aq) + MnO2 (s) → MnCl2 (aq) + Cl2 (g) + 2 H2O (l)

This is an oxidation-reduction (redox) reaction:

MnIV + 2 e- → MnII (reduction)

2 Cl-I - 2 e- → 2 Cl0 (oxidation)

MnO2 is an oxidizing agent, HCl is a reducing agent.

Reactants:

HCl – Chlorane, Hydrogen chloride

Other names: Hydrochloric acid
Appearance: Colorless, transparent liquid, fumes in air if concentrated; Colorless gas; Colourless compressed liquefied gas with pungent odour; Colorless to slightly yellow gas with a pungent, irritating odor. [Note: Shipped as a liquefied compressed gas.]

MnO2 – Manganese oxide, Manganese(IV) oxide

Other names: Manganese dioxide, Pyrolusite, Hyperoxide of manganese

Appearance: Brown-black solid Black-to-brown powder

Products:

MnCl2 – Manganese(II) chloride, Manganese dichloride

Other names: Manganous chloride, Manganous dichloride Manganese(II) chloride (1:2)

Appearance: Pink solid (tetrahydrate)

Cl2

Names: Chlorine, Molecular chlorine

Appearance: Greenish-yellow compressed liquefied gas with pungent odour ; Greenish-yellow gas with a pungent, irritating odor. [Note: Shipped as a liquefied compressed gas.]

H2O – Water, oxidane

Other names: Water (H2O) Hydrogen hydroxide (HH or HOH) Hydrogen oxide

Appearance: White crystalline solid, almost colorless liquid with a hint of blue, colorless gas

Explanation:

6 0

2 years ago

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