I need numbers 8 and 9. Thank you.

What is the molar mass, in grams, of a mole of an element equal to?

prohojiy [21]

Technically molar mass cannot be in grams, it is in grams per mole. and it refers to a specific number of molecules of a substance, therefore substances have different molar masses because the elements have different weights. for example having 10 water molecules would be a lot heavier than having 10 air molecules

6 0

3 years ago

Help me please| (• ◡•)|

nika2105 [10]

Answer:

the importance of freezing in out daily lives

If you live in Canada you would know why the freezing and melting point of water is important. In the winter when it rises above freezing and rains then drops below freezing again, that water will freeze and cause the roads and sidewalks to be hazardous.

On a recent trip to the US I looked up the weather forecast and it was in Fahrenheit. I couldn't remember exactly what the freezing point of water was in Fahrenheit so I had to look it up. The forecast was for precipitation so I needed to know if it was likely to fall as rain, freezing rain (very dangerous) or snow.

When I use my windshield wipers I need to know that it's not pure water that's being squirted out. In the winter I need to know that there is anti-freeze in it so it won't freeze in the lines.

When I'm hiking up a mountain wearing a Camelback hydration system I need to know if the temperatures will drop below freezing or I will not have any water to drink as the water line will freeze. Same with uninsulated water bottles, and your sandwich.

Explanation:

the importance of evaporation and condensation

Evaporation happens when a liquid substance becomes a gas. When water is heated, it evaporates. The molecules move and vibrate so quickly that they escape into the atmosphere as molecules of water vapor.

Evaporation is a very important part of the water cycle. Heat from the sun, or solar energy, powers the evaporation process. It soaks up moisture from soil in a garden, as well as the biggest oceans and lakes. The water level will decrease as it is exposed to the heat of the sun.

Although the level of a lake, pool, or glass of water will decrease due to evaporation, the escaped water molecules dont disappear. They stay in the atmosphere, affecting humidity, or the amount of moisture in the air.

6 0

3 years ago

When the compound BaCl2 forms , what happens to the Ba and Cl ions

Korvikt [17]

Ba stays as Ba+2 and Cl stays as Cl-

6 0

3 years ago

Read 2 more answers

The compound dioxane, which is used as a solvent in various industrial processes is composed of C,H, and O atoms. Combustion of

Lady_Fox [76]

Answer:

The correct formula of dioxane is C₄H₈O₂.

Explanation:

Given data:

mass of dioxane= 2.23 g

mass of water = 1.802 g

mass of carbon dioxide = 4.401 g

molar mass of dioxane = 88.1 g / mol

Molecular formula of dioxane = ?

Solution:

percentage of carbon = (4.401 g/2.23 g ) × (12 /44) × 100

= (1.98 × 0.273) × 100 = 54.1

percentage of hydrogen = (1.802 g/ 2.23 g) × (2.016 /18.016) × 100

= (0.81 × 0.112) × 100 = 9.072

percentage of oxygen = 100 - (54.1 + 9.072)

= 100 - 63.172 = 36.828

Now we will determine the number of grams atoms of carbon, hydrogen and oxygen.

No. of gram atoms of carbon = 54.1 /12 = 4.51

No. of gram atoms of hydrogen = 9.072 / 1.008 = 9

No. of gram atoms of oxygen = 36.828 / 16 = 2.302

Atomic ratio:

C :H :O 4.51/ 2.302 : 9 / 2.302 : 2.302 /2.302

C :H :O 2 : 4 : 1

Molecular formula:

Molecular formula = n × (empirical formula)

n = molar mass of compound / empirical formula mass

empirical formula mass= 2 × 12 + 4 × 1.008 + 1 × 16

empirical formula mass= 24+ 4.032 +16 = 44.032

n = 88.1 / 44.032 = 2

Molecular formula = n × (empirical formula)

Molecular formula = 2 × (C₂H₄O)

Molecular formula = C₄H₈O₂

8 0

3 years ago

Filtration, decantation, and evaporation are examples of

Tju [1.3M]

<span>An element is made of only one kind of atom, while a compound contains the atoms of two or more elements. For example, gold is made of only one kind of atom, so it is an element, but water is a mix of hydrogen and oxygen, so it is a compound.</span>

4 0

3 years ago