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2 years ago

This is the number of protons and neutrons i the nucleus of any atom

Chemistry

1 answer:

icang [17]2 years ago

4 0

Answer:

The mass number is defined as the total number of protons and neutrons in an atom. Consider Table below which shows data from the first six elements of the periodic table. Consider the element helium. Its atomic number is 2, so it has two protons in its nucleus.

Explanation:

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State two differences between metals and non metals with respect to their

Naya [18.7K]

Answer:

Physical Properties

1. Metals are shiny but most non - metals lack this property.

2. Metals are able to deform under compression (malleable) but most non - metals lack this property.

Chemical Properties

1. Metals are good conductorsof heat and electricity but most non - metals are insulators.

2. Metals, when exposed to water atmospheric oxygen tend to rust but non - metals lack this chemical property

7 0

2 years ago

The temperature of evaporation is much higher for water than for alcohol. Without knowing more about the chemistry of alcohol, w

3241004551 [841]

Answer:

Explanation:

Alcohols are organic molecules characterized majorly by the presence of the OH group in their molecule. The OH group is majorly responsible for several of their characteristics. This include the formation of hydrogen bonds between alcohol molecules. While this makes them more inorganic than most organic compounds, comparatively the hydrogen bonding formed in alcohols is not as strong as that which is present in water.

The higher strength of the hydrogen bonding is responsible for some comparable properties. While water boils at a temperature of 100 degrees Celsius, alcohol boils at a temperature of 78 degrees Celsius. This is an evidence to the fact that hydrogen bonding in alcohol is less stronger that that in water.

4 0

3 years ago

You have 16.0 g of some compound and you perform an experiment to remove all of the oxygen, 11.2 g of iron is left. What is the

Makovka662 [10]

The empirical formula of this compound is $Fe_2O_3$

<h3>Empirical formula </h3>

To calculate the empirical formula of a compound, the value of moles of each element is needed.

As we have the information of the mass value, we will use the molar mass expression, which corresponds to:

$MM_O = 16g/mol\\MM_Fe = 55.8g/mol$

$MM = \frac{m}{mol}$

$16 = \frac{4.8}{x}$

$x = 0.3mol$

$55.8=\frac{11.2}{x}\\x = 0.2$

As the value of the empirical formula must be an integer, simply multiply the two values by a common factor:

$O = 0.3 \times 10 = 3\\Fe = 0.2 \times 10 = 2$

$Fe_2O_3$

So, the empirical formula of this compound is $Fe_2O_3$ .

Learn more about empirical formula: brainly.com/question/1247523

3 0

1 year ago

There are two naturally occurring isotopes of copper. 63cu has a mass of 62.9296 amu. 65cu has a mass of 64.9278 amu. determine

SSSSS [86.1K]

1) You need to use the atomic mass of copper.

You can find it in a periodic table. It is 63.546 amu.

2) The atomic mass is the weigthed mass of the different isotopes.

This is, the atomic mass of one element is the atomic mass of each isotope times its corresponding abundance:

=> atomic mass of the element = abundance isotope 1 * atomic mass isotope 1 + abundance isotope 2 * atomic mass isotope 2 + ....+abundance isotope n * atomic mass isotope n.

3) The statement tells there are two isotopes so the abundance of one is x and the abundance of the other is 1 - x

=> 63.546 amu = x * 62.9296 amu + (1-x)*64.9278

=> 63.546 = 62.9296x + 64.9278 - 64.9278x

=> 64.9278x - 62.9296 = 64.9278 - 63.546

=> 1.9982x = 1.3818

=> x = 1.3818 / 1.9982 = 0.6915 = 69.15%

=> 1 - x = 1 - 0.6915 = 0.3085 = 30.85%

Answer:

Cu-63 69.15%;

Cu-65 : 30.85%

3 0

2 years ago

An element X combines with oxygen to form a compound of formula XO2. If 24.0 grams of element X combines with exactly 16.0 grams

tensa zangetsu [6.8K]

Answer:

atomic mass of X is 48.0 amu

Explanation:

Let y be the atomic mass of X

Molar mass of O_2 is = 2×16 = 32 g / mol

X + O2 -----> XO_2

According to the equation ,

y g of X reacts with 32 g of O_2

24 g of X reacts with Z g of O_2

Z = ( 32×24) / y

But given that 24.0 g of X exactly reacts with 16.0 g of O_2

So Z = 16.0

⇒ (32×24) / y = 16.0

⇒ y = (32×24) / 16

y= 48.0

So atomic mass of X is 48.0 amu

4 0

3 years ago