All categories

3 years ago

Match these items with their examples.

Chemistry

2 answers:

kiruha [24]3 years ago

7 0

Here you go! Feel free to ask questions!

Alexus [3.1K]3 years ago

7 0

Answer:

1. liquid solution: soda

2. solid solution: Steel

3. compound: Salt

4. colloid: milk

5. element: aluminum foil

Explanation:

1. Soda is a mixture of water, carbon dioxide gas, and solid sugar. Sugar is dissolved in water, and carbon dioxide is dissolved in water under pressure

2. Alloys, like steel, are solid solutions made up of one metal and one or more metal or non-metal elements.

3. Salt is an ionic compound composed by sodium and chlorine.

4. In a colloid large molecules or ultramicroscopic particles of one substance are dispersed through a second substance; at first sight they are confused with solutions because dispersed molecules are not evident . Milk is a mixture of liquid fat-globules dispersed and suspended in water

5. Aluminum foil is olly composed by one element, aluminium

You might be interested in

How does pressure affect an organism plants?

sleet_krkn [62]

Answer:

Turgor pressure in plants. Turgor pressure within cells is regulated by osmosis and this also causes the cell wall to expand during growth.

Explanation:

I hope that helps

7 0

2 years ago

Predict the sign of ΔS° for 2NO2(g) LaTeX: \longrightarrow⟶ N2O4(g) CaCO3(s) + 2HCl(aq) LaTeX: \longrightarrow⟶ CaCl2(aq) + H2O(

prisoha [69]

Answer: a. $2NO_2(g)\rightarrow N_2O_4(g)$ : $\Delta S$ is negative

b. $CaCO_3(s)+2HCl(aq)\rightarrow CaCl_2(aq)+H_2O(l)$ : $\Delta S$ is negative

c. $Ag^+(aq)+Cl^-(aq)\rightarrow AgCl(s)$ : $\Delta S$ is negative

Explanation:

Entropy is the measure of randomness or disorder of a system. If a system moves from an ordered arrangement to a disordered arrangement, the entropy is said to decrease and vice versa

a) $2NO_2(g)\rightarrow N_2O_4(g)$

In this reaction 2 moles of gaseous reactants are converting to 1 mole of gaseous products. The randomness will decrease and hence entropy will also decrease. Thus $\Delta S$ is negative.

b) $CaCO_3(s)+2HCl(aq)\rightarrow CaCl_2(aq)+H_2O(l)$

In this reaction solid reactants are converting to aqueous products. The randomness will increase and hence entropy will also increase. Thus $\Delta S$ is positive.

c) $Ag^+(aq)+Cl^-(aq)\rightarrow AgCl(s)$

In this reaction aqueous reactants are converting to solid products. The randomness will decrease and hence entropy will also decrease. Thus $\Delta S$ is negative

3 0

3 years ago

Balance the equation. Mg3(PO4)2+? C → ? Mg3P2+? CO , using the smallest possible integers. What is the sum of the coefficients i

Nuetrik [128]

Answer:

Sum of coefficients in balanced equation is 18

Explanation:

Unbalanced equation: $Mg_{3}(PO_{4})_{2}+C\rightarrow Mg_{3}P_{2}+CO$

Balance O: $Mg_{3}(PO_{4})_{2}+C\rightarrow Mg_{3}P_{2}+8CO$

Balance C: $Mg_{3}(PO_{4})_{2}+8C\rightarrow Mg_{3}P_{2}+8CO$

Balanced equation: $Mg_{3}(PO_{4})_{2}+8C\rightarrow Mg_{3}P_{2}+8CO$

Sum of coefficients in balanced equation = (1+8+1+8) = 18

So, option (4) is correct.

8 0

3 years ago

An important step in the synthesis of nitric acid is the conversion of ammonia to nitric oxide. 4NH3(g) + 5O2(g) --> 4NO(g) +

Rina8888 [55]

Answer:

The ΔH°rxn for this reaction is -905.9 kJ

Explanation:

Step 1: Balanced reaction:

4NH3(g) + 5O2(g) --> 4NO(g) + 6H2O(g)

Step 2: Given data

ΔH°f [NH3(g)] = –45.9 kJ/mol

ΔH°f [NO(g)] = 90.3 kJ/mol

ΔH°f [H2O(g)] = –241.8 kJ/mol

ΔH°f of O2 is defined to be zero

Step 3: Calculate ΔH°rxn

ΔH°rxn = ΔH°products - ΔH°reactants

ΔH°rxn = ((4*90.3) + 6*-(241.8)) - 4*(-45.9) = -905.9 kJ

The ΔH°rxn for this reaction is -905.9 kJ

8 0

3 years ago

Click on the graph to show how rate of reaction is usually related to activation energy

serious [3.7K]

Answer: Graph 3

Explanation:

Activation energy is the level of energy required by a chemical reaction for the reaction to proceed.

A higher Activation energy will translate to a lower reaction rate because less molecules will be able to achieve this required energy needed for them to react. A lower activation energy however will enable a faster reaction time because more molecules will achieve the required energy.

Higher Activation energy = Lower Reaction rate

Lower Activation energy = Higher reaction rate

This is what Graph 3 shows so it is correct.

8 0

2 years ago