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3 years ago

What is not represented by a balanced chemical equation?

Chemistry

1 answer:

astraxan [27]3 years ago

5 0

Answer is: 4) The same subscripts are on each side of the equation.

For example, balanced chemical reaction:

2Mg + O₂ → 2MgO.

1) The same number of atoms is on each side of the equation: two magnesium atoms and two oxgen atoms.

2) The formulas for all substances are correct: in magnesium oxide (MgO), magnesium has oxidation number +2 and oxygen -2, so formula is good, because compound must be neutral.

3) The same mass is represented on each side of the equation: because there is same number of atoms, the mass is the same.

4) The same subscripts are on each side of the equation: oxygen does not have same subscripts.

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Un mol de amoniaco Tiene una masa molar de 17 g y ocupa un volumen de 22.4 l qué volumen ocupa el 50 g amoniaco en condiciones n

mr_godi [17]

Answer:

V = 65.81 L

Explanation:

En este caso, debemos usar la expresión para los gases ideales, la cual es la siguiente:

PV = nRT (1)

Donde:

P: Presion (atm)

V: Volumen (L)

n: moles

R: constante de gases (0.082 L atm / mol K)

T: Temperatura (K)

De ahí, despejando el volumen tenemos:

V = nRT / P (2)

Sin embargo como estamos hablando de condiciones normales de temperatura y presión, significa que estamos trabajando a 0° C (o 273 K) y 1 atm de presión. Lo que debemos hacer primero, es calcular los moles que hay en 50 g de amoníaco, usando su masa molar de 17 g/mol:

n = 50 / 17 = 2.94 moles

Con estos moles, reemplazamos en la expresión (2) y calculamos el volumen:

V = 2.94 * 0.082 * 273 / 1

4 0

3 years ago

Fill in the missing spaces in the chart. Will give brainliest.

lana [24]

Explanation:

9/4 Be +2 (the 9 and 4 are stacked next to Be). Atomic #: 4

Mass #: 9, # protons: 4, # neutrons: 5, #electrons: 2.

31/15 P (31 is stacked over 15 next to the P). Atomic #: 15,

Mass #: 31, # protons: 15, # neutrons: 16, # electrons: 15.

3 0

3 years ago

Which causes an air conditioner to turn on

vfiekz [6]

Answer:

C.)house temperature increases cause the bimetallic coil to expand

Explanation:

A bimetallic strip is used in an air conditioner as a regulator. It is made up of two metals that behaves differently to a change in temperature.

To turn on the air conditoner, the circuit must be complete. When the temperature is high in a room, bimetallic strip responds by expanding and bending to complete the circuit. This puts on the air conditioner and the house begins to cool through exchange of warm and cold air.

When the temperature is too cold, the strip contracts and straightens. This process disconnects the circuit and the air conditioning system ceases to work.

3 0

3 years ago

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A 33.0 mL sample of 1.15 M KBr and a 59.0 mL sample of 0.660 M KBr are mixed. The solution is then heated to evaporate water unt

Oksi-84 [34.3K]

Answer:

We need 13.06 grams of silver nitrate to precipitate out silver bromide in the final solution

Explanation:

Step 1: Data given

Sample 1: The 1.15 M sample has a volume of 33.O mL

Sample 2: The 0.660 M sample has a volume of 59.0 mL

Molar mass of KBr = 119 g/mol

Molar mass of AgNO3 = 169.87 g/mol

Step 2: Calculate number of moles for both samples

Number of moles = Molarity * Volume

Sample 1: 1.15 M * 33 *10^-3 L = 0.03795 moles

Sample 2: 0.660 M *59*10^-3 L = 0.03894 moles

Total mol KBr = 0.03795 + 0.03894 = 0.07689 moles

Step 3: Calculate total mass

mass = Number of moles * Molar mass

mass = 0.07689 moles * 119 g/moles = 9.15 grams ( in 55mL)

Step 4: Calculate moles of AgBr

AgNO3 reacts with KBr

KBr(aq) + AgNO3(aq) → AgBr(s) + KNO3(aq)

1 mole of KBr consumed, needs 1 mole of AgNO3 to produce 1 mole of AgBr and 1 mole of KNO3

So 0.07689 moles of KBr wll need 0.07689 moles of AgNO3

Step 5: Calculate mass of silver nitrate

mass of AgNO3 = Moles of AgNO3 * Molar mass of AgNO3

mass of AgNO3 = 0.07689 moles * 169.87 g/mol = 13.06 grams

We need 13.06 grams of silver nitrate to precipitate out silver bromide in the final solution

8 0

3 years ago

Which statement is true about the compound ammonium sulfate [(NH4)2SO4] ?

BabaBlast [244]

Answer:

It is a salt of two polyatomic ammonium ions and one polyatomic sulfate ion

Explanation:

Ammonium Sulfate is an ionic compound formed by two polyatomic ions, Ammonium NH+4 and Sulfate SO−4 . ... Therefore, it will take two +1 ammonium ions to balance the one -2 sulfate ion. This will make the formula for Ammonium Sulfate (NH4)2SO4

4 0

3 years ago

Read 2 more answers