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4 years ago

What is the definition of a solution

1 answer:

4 0

A solution means that you're trying to solve (or deal) with a situation.

For example, if you're having trouble trying to solve a math problem, that means that you're trying to figure out that problem.

You might be interested in

Write a balanced molecular equation describing each of the following chemical reactions. (a) Solid calcium carbonate is heated a

viktelen [127]

Answer:

a. CaCO₃ (s) → CaO (s) + CO₂(g) ΔH

b. 2C₄H₁₀ (g) + 13O₂(g) → 8CO₂ (g) + 10H₂O(g)

c. MgCl₂ (aq) + 2NaOH(aq) → Mg(OH)₂ (s) ↓ + 2NaCl (aq)

d. 2H₂O(g) + 2Na(s) → 2NaOH(s) + H₂(g)

Explanation:

We identify the compound by the formula and we make the reaction with the phases of each reactant and product:

a. CaCO₃ (s); CaO (s), CO₂(g)

The reaction is: CaCO₃ (s) → CaO (s) + CO₂(g) ΔH

We add the ΔH symbol because there is heat added to the reaction, which means a enthalpy change

b. C₄H₁₀ (g), O₂(g) ; CO₂ (g), H₂O(g)

The reaction is: 2C₄H₁₀ (g) + 13O₂(g) → 8CO₂ (g) + 10H₂O(g)

In order to balance, we add 10 moles to water, so in total we have 20 H. Therefore we need 2 moles of butane to have 20 H, but we also have 8 C. So we need 8 C for the CO₂. By the end we have 16 O in CO₂ plus 10 O from water. In conclussion we need 13 O₂ in the reactant side to get the final balance

c. MgCl₂ (aq), NaOH(aq) ; Mg(OH)₂ (aq) , NaCl

The reaction is: MgCl₂ (aq) + 2NaOH(aq) → Mg(OH)₂ (s) ↓ + 2NaCl (aq)

As the Mg(OH)₂ is solid, it indicates that we made a precipitate in the reaction (That's why we add ↓, in the product side). We need 2NaCl, to balance the Cl and 2 NaOH to balance the Na.

Finally the Mg is balanced

d. H₂O(g), Na(s) ; NaOH (s), H₂(g)

Reaction is: 2H₂O(g) + 2Na(s) → 2NaOH(s) + H₂(g)

We add 2 water in order to balance the hydrogen gas, but we need a 2 in the hydoxide. Finally we will balance the Na with also a 2.

7 0

3 years ago

What is the pH of a 1 ´ 10-5 M KOH solution?

melisa1 [442]

KOH -------------> K⁺ + OH⁻

pOH = - log [ OH⁻ ]

pOH = - log [ 1 x 10⁻⁵ ]

pOH = 5

pH + pOH = 14

pH + 5 = 14

pH = 14 - 5

pH = 9

hope this helps!

3 0

3 years ago

The chemical formula of aspirin is C9H8O4. What is the mass of 0.40 mol<br> of aspirin?

dybincka [34]

Answer:

$\boxed {\boxed {\sf About \ 72 \ grams }}$

Explanation:

To convert from moles to grams, we must use the molar mass (also known as the gram formula mass).

First, look up the molar masses of the elements in the formula.

C: 12.011 g/mol
H: 1.008 g/mol
O: 15.999 g/mol

Next, multiply by the subscript, because it tells us the number of atoms of each element in the formula.

C₉: 4(12.011 g/mol)= 108.099 g/mol
H₈: 8(1.008 g/mol)= 8.064 g/mol
O₄: 4(15.999 g/mol)= 63.996 g/mol

Add the values.

108.099 + 8.064+63.996=180.159 g/mol

Use this molar mass as a ratio.

$\frac {180.159 \ g \ C_9H_8O_4}{1 \ mol \ C_9H_8O_4}$

Multiply by the given number of moles, 0.40

$0.40 \ mol \ C_9H_8O_4 *\frac {180.159 \ g \ C_9H_8O_4}{1 \ mol \ C_9H_8O_4}$

The units moles of aspirin cancel.

$0.40 *\frac {180.159 \ g \ C_9H_8O_4}{1 }$

$72.0636 \ g \ C_9H_8O_4$

The original number of moles has 2 sig figs (4 and 0), so answer must have the same. For the number we calculated, it is the ones place. The 0 in the tenth place tells us to leave the 2.

$72 \ g$

5 0

3 years ago

Which material is the least likely to be recognized as a mixture by looking at it under a microscope? a suspension a colloid a h

viktelen [127]

Answer:

A homogeneous mixture for sure

4 0

3 years ago

Read 2 more answers

What is the simplest formula of a solid containing a, b, and c atoms in a cubic lattice in which the a atoms occupy the corners,

Ilya [14]

Answer:

c. abc₃

Step-by-step explanation:

1. a atoms

There are eight corners, each containing an a atom.

No. of a atoms = 8 × ⅛

No. of a atoms = 1

=====

2. b atoms

There is one central b atom.

=====

3. c atoms

There are six faces, each containing a c atom.

No. of a atoms = 6 × ½

No. of c atoms = 3

=====

4. Formula

The simplest formula is abc₃.

4 0

4 years ago