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¿El agua salada es una mezcla homogénea o heterogénea?

mr_godi [17]

Answer:

Homogénea

Explanation:

Una mezcla homogénea ocurre cuando se unen dos o más sustancias y no se pueden identificar después de ser unidas

En este caso no se logran identificar los compuestos

7 0

3 years ago

What is the molar mass of methane (CH4)? What is the molar mass of methane (CH4)?

Likurg_2 [28]

16.0424 g/mol is the answer sir or ma’am

6 0

2 years ago

A dark brown binary compound contains oxygen and a metal. It is 13.38% oxygen by mass. Heating it moderately drives off some of

Leto [7]

Answer:

a) Mass of O in compound A = 32.72 g

Mass of O in compound B = 21.26 g

Mass of O in compound C = 15.94 g

b) Compound A = MO2

Compound B = M3O4

Compound C = MO

c) M = Pb

Explanation:

Step 1: Data given

A binairy compound contains oxygen (O) and metal (M)

⇒ 13.38 % O

⇒ 100 - 13.38 = 86.62 % M

After heating we get another binairy compound

⇒ 9.334 % O

⇒ 100 - 9.334 = 90.666 % M

After heating we get another binairy compound

⇒ 7.168 % O

⇒ 100 - 7.168 = 92.832 % M

The first compound has an empirical formula of MO2

⇒ 1 mol M for 2 moles O

Step 2: Calculate amount of metal and oxygen in each

compound A: M = m1 *0.8662 O = m1 *0.1338

compound B: M = m2 *0.90666 O = m2 *0.09334

compound C: M = m3 *0.92832 O = m3 *0.07168

Step 3: Calculate mass of oxygen with 1.000 grams of M

Compound A: 1.000g * 0.1338 m1gO / 0.8662m1gMetal = 0.1545

Compound B: 1.000g * 0.09334 m2gO / 0.90666m2gMetal = 0.1029

Compound C: 1.000g * 0.07168 m3gO / 0.92832m3gMetal = 0.07721

Step 4:

1 mol MO2 has 1 mol M and 2 moles O

m1 = (mol O * 16)/0.1338 m1 = 239.2 grams

1 mol M = 0.8632*239.2 = 206.48

0.90666m2 = 206.48 ⇒ m2 = 227.74 g

0.92832m3 = 206.48 ⇒ m3 = 222.42 g

Step 5: Calculate mass of O

Mass of O in compound A = 239.2 - 206.48 = 32.72 g

Mass of O in compound B = 227.74 - 206.48 = 21.26 g

Mass of O in compound C = 222.42- 206.48 = 15.94 g

Step 6: Calculate moles

Moles of O in compound A ≈ 2

⇒ MO2

Moles of O in compound B = 21.26 / 16 ≈ 1.33

⇒ M3O4

Moles of O compound C = 15.94 /16 ≈ 1 moles

⇒ MO

Step 7: Calculate molar mass

The mass of 1 mol metal is 206.48 grams ⇒ molar mass ≈ 206.48 g/mol

The closest metal to this molar mass is lead (Pb)

6 0

3 years ago

Cuantos gramos de hidróxido de calcio se necesitan para preparar 875ml de solución al 2M

PtichkaEL [24]

Answer:

129,66 g

Explanation:

Desde,

Número de moles = concentración * volumen

concentración = 2 M

volumen = 875 ml

Número de lunares = 2 * 875/1000

Número de lunares = 1,75 moles

Número de moles = masa / masa molar

masa molar de hidróxido de calcio = 74.093 g / mol

1,75 moles = masa / 74,093 g / mol

masa = 1,75 moles * 74,093 g / mol

masa = 129,66 g

7 0

3 years ago

Specify which atoms, if any, bear a formal charge in the Lewis structure given and the net charge for the species.

ozzi

Answer :

Formal charge on C: (-1)

Formal charge on N: (0)

Net charge: (-1)

Explanation :

First we have to determine the Lewis-dot structure of $CN^-$ .

Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.

In the Lewis-dot structure the valance electrons are shown by 'dot'.

The given molecule is, $CN^-$

As we know that carbon has '4' valence electrons and nitrogen has '5' valence electrons.

Therefore, the total number of valence electrons in $CN^-$ = 4 + 5 + 1= 10

According to Lewis-dot structure, there are 6 number of bonding electrons and 4 number of non-bonding electrons.

Now we have to determine the formal charge for each atom.

Formula for formal charge :

$\text{Formal charge}=\text{Valence electrons}-\text{Non-bonding electrons}-\frac{\text{Bonding electrons}}{2}$

$\text{Formal charge on C}=4-2-\frac{6}{2}=-1$

$\text{Formal charge on N}=5-2-\frac{6}{2}=0$

Net charge = -1 + 0 = -1

4 0

4 years ago