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3 years ago

Which two statements about composite materials are true?

2 answers:

5 0

I believe that the best answer to the choices given in your question are:

2.They have the same or similar properties as the materials used to make them.1.They’re made up of more than one substance.
Thank you for posting here at Brainly.I hope I have answered your question. Have a nice day ahead.

gregori [183]3 years ago

4 0

The correct answer is:

They’re made up of more than one substance.

They have the same or similar properties as the materials used to make them.

Explanation:

A composite material is a material constituted from two or more constituent materials with significantly complex physical or chemical properties that, when mixed, produce a material with properties distinct from the individual elements.

You might be interested in

Roundup, an herbicide manufactured by Monsanto, has the formula C3H8NO5P. How many moles of molecules are there in a 783.5-g sam

anastassius [24]

First, is to solve the molar mass of the herbicide, with a formula
C3H8NO5P
C3 = 12 ( 3 ) = 36
H8 = 1 ( 8 ) = 8
N = 14
O5 = 16 ( 5 ) = 80
P = 31
so in total the molar mass of C3H8NO5P is 36 + 8 + 14 + 80 + 31 = 169 g/mol

number of moles = 783.5 g ( 1 mol / 169 g)
number of moles = 4.64 mol C3H8NO5P

8 0

3 years ago

Please help, due tomorrow! ツ

oksano4ka [1.4K]

There are two kinds of mixtures

a) homogeneous : the boundary of the two components is not physically distinct

b) heterogeneous:the boundary of the two components is physically distinct

the following separation techniques are common for mixtures

1) filtration: if the two components are forming heterogeneous mixture we can separate them by filtration.

2) boiling: if boiling point of one of the components is less than other

3) magnetic separation: if one of the component is magnetic

4)sieve method: for solid components with difference in size of particles

5) hand picking

Thus the correct match will be as shown in the figure

3 0

3 years ago

You are asked to prepare 500 mL 0.200 M acetate buffer at pH 5.00 using only pure acetic acid ( MW=60.05 g/mol, pKa=4.76), 3.00

Vilka [71]

Answer:

You need to weight 6,005 g of acetic acid

Explanation:

Using Henderson-Hasselbalch formula you will obtain:

5,00 = 4,76 +log₁₀ $\frac{[Ac^-]}{[Acac]}$

Where Ac⁻ is the salt of acetic acid (Acac).

Solving:

1,738 = $\frac{[Ac^-]}{[Acac]}$ (1)

Also, yo know that:

0,200 M = [Ac⁻] + [Acac] (2)

Replacing (2) in (1):

[Acac] = 0,0730 M.

Thus:

[Ac⁻] = 0,127 M

The moles of each compound are:

Acac = 0,0730 M × 0,500 L = 0,0365 mol

Ac⁻ = 0,127 M × 0,500 L = 0,0635 mol

To prepare these moles it is necessary to use:

Acac + NaOH → AcNa + H₂O

The initial moles of Acac must be:

0,0365 moles + 0,0635 moles = 0,100 moles

To obtain 0,0635 moles of Ac⁻ you need to take this quantity of NaOH moles.

Thus, to obtain a acetate buffer of 5,00 you need to add 0,100 moles of acetic acid and 0,0635 moles of NaOH because This NaOH will react with acetic acid producing 0,0635 moles of Ac⁻ and surplus 0,0365 moles of acetic acid.

Now, to obtain 0,100 moles of acetic acid from pure acetic acid:

0,100 moles × $\frac{60,05 g}{1 mol}$ = 6,005 g

You need to weight 6,005 g of acetic acid

I hope it helps!

7 0

4 years ago

A student mixed 50 ml of 1.0 M HCl and 50 ml of 1.0 M NaOH in a coffee cup calorimeter and calculated the molar enthalpy change

MrRa [10]

Answer:

-54 kJ/mol

Explanation:

Given that:

A student mixed 50 ml of 1.0 M HCl and 50 ml of 1.0 M NaOH in a coffee cup calorimeter and calculated the molar enthalpy change of the acid-base neutralization reaction to be –54 kJ/mol

i.e

50 ml of 1.0 M HCl + 50 ml of 1.0 M NaOH -----> -54 kJ/mol

If he repeat the same experiment with :

100 ml of 1.0 M HCl + 100 ml of 1.0 M NaOH. ------> ????

From The experiment; the molar enthalpy of change of the acid-base neutralization reaction will be -54 kJ/mol

This is because : The second reaction requires 50 ml in order to neutralize the reaction, then the remaining 50 ml will be excess, Hence, there is no change in the enthalpy of the reaction.

Similarly; we can assume that :

In the first reaction; P moles of is used to liberate Q kJ heat ; then the change in molar enthalpy will be Q/P (kJ/mol).

SO; when he used 100 ml ;

then the amount of moles used is double, likewise the heat liberated will be doubled ;

So;

2P moles is used to liberate 2Q kJ heat ;

2P/2Q = Q/P ( kJ/mol) = -54 kJ/mol

8 0

3 years ago

PLEASE HELP ASAP IM BEGGING YOU!!!!!!!!!!

navik [9.2K]

The answer is the last one

3 0

4 years ago