While in science class a student measured a cube. She

Plz Help! What are antibodies and what role do vaccines play in producing them?

ladessa [460]

Answer:

Antibodies are types of proteins in the body that can prevent diseases. Once a vaccine is introduced into the bloodstream, it immediately causes the production of antibodies to occur by using T-cells and B lymphocytes, or at least, most vaccines work like that.

Explanation:

6 0

2 years ago

Which of the following is not true? a. The freezing point of sea water is lower than the freezing point of pure water. b. The bo

Anna007 [38]

Answer:

The false statement is b.

The boiling point of a water sample from the Salt Lake is lower than the boiling point of pure water

Explanation:

This excersise refers to colligative properties.

Boiling point refers to the property of boiling point elevation. In a solution of ions, as water sea or water from lakes, the boiling point will be higher than water pure.

It is logical to say that, because these sort of water have ions. Remember that colligative properties depends on the solute particles.

T° boiling solution - T° pure solvent = Kb . m . i

In the freezing point depression, we have the oppossite of boiling point elevation. Freezing point of solution is lower than pure solvent, according to this:

T° freezing pure solvent - T° freezing solution = Kc . m . i

We have to always consider the i, which means Van't Hoff factor, number of ions dissolved in solution. As the i is higher, the freezing point of solution will be lower, and the boiling point of solution will be higher.

They are true statement a and c.

In solution of., [NaCl] = 0.1M, as it is a higher concentration, the molality is also higher than a solution of [NaCl] = 0.05.

As water sample form Salt Lake has certain ions, it is logical to say that the boiling point of this water is higher than boiling point of pure water.

5 0

2 years ago

What would indicate that a physical change takes place when cooper is drawn into wire

amid [387]

Answer:

When a copper is drawn into wire the only change that occurs is change in its shape and size no change will take place into its composition that is the wires are still possessing the properties of copper metal. Thus, a physical change takes place when copper is drawn into wire.

4 0

2 years ago

What is glucose? How is it formed?

Alik [6]

Glucose is a simple sugar with the molecular formula C6H12O6. It is a carbohydrate.

6 0

2 years ago

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Carbon tetrachloride reacts at high temperatures with oxygen to produce two toxic gases, phosgene and chlorine. CCl4(g) + (1/2)O

madam [21]

The question is incomplete, here is the complete question:

Carbon tetrachloride reacts at high temperatures with oxygen to produce two toxic gases, phosgene and chlorine.

$CCl_4(g)+\frac{1}{2}O_2(g)\rightleftharpoons COCl_2(g)+Cl_2(g);K_c=4.4\times 10^9$ at 1,000 K

Calculate Kc for the reaction $2CCl_4(g)+O_2(g)\rightleftharpoons 2COCl_2(g)+2Cl_2(g)$

Answer: The value of $K_c'$ for the final reaction is $1.936\times 10^{19}$

Explanation:

The given chemical equations follows:

$CCl_4(g)+\frac{1}{2}O_2(g)\rightleftharpoons COCl_2(g)+Cl_2(g);K_c$

We need to calculate the equilibrium constant for the equation, which is:

$2CCl_4(g)+O_2(g)\rightleftharpoons 2COCl_2(g)+2Cl_2(g)$

As, the final reaction is the twice of the initial equation. So, the equilibrium constant for the final reaction will be the square of the initial equilibrium constant.

The value of equilibrium constant for net reaction is:

$K_c'=(K_c)^2$

We are given:

$K_c=4.4\times 10^9$

Putting values in above equation, we get:

$K_c'=(4.4\times 10^9)^2=1.936\times 10^{19}$

Hence, the value of $K_c'$ for the final reaction is $1.936\times 10^{19}$

3 0

2 years ago