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3 years ago

If an atom of an element has a mass number of 45 and it has 20 neutrons in its nucleus, what is the atomic number of the

Chemistry

1 answer:

HACTEHA [7]3 years ago

3 0

Answer:

Explanation:

uestion

If an atom of an element has a mass number of 45 and it has 20 neutrons in its nucleus, what is the atomic number of the

element?

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Will magnesium and fluorine atoms most likely form an ionic bond or a covalent bond?

Andreas93 [3]

Answer:

Ionic bond

Explanation:

The magnesium atom gives up 2 electrons to form a magnesium ion, Mg2+ . The two electrons are transferred to fluorine atoms to form two fluoride ions, F–.

6 0

3 years ago

Read 2 more answers

When the procedure calls for making a more dilute solution of an acid, or mixing an acid with other solutions, what is the corre

stiks02 [169]

Explanation:

Whenever we need to make a dilute solution of an acid then it is necessary to add water or non-acidic component into the acid first. This is because addition of water or non-acidic component directly into the acid could be highly exothermic in nature.

As a result, the acid can splutter and can cause burning of skin and other serious damage.

So, in order to avoid such type of damage the addition of water or non-acidic component into the acid actually helps to minimize the heat generated.

Thus, we can conclude that correct order of steps for making a more dilute solution of an acid is that either add all of the water or non-acid component first, or add a significant portion, before adding the acid to the mixture.

8 0

2 years ago

Find the final equilibrium temperature when 15.0 g of milk at 13.0 degrees c is added to 148 g of coffee with a temperature of 8

user100 [1]

According to zeroth law of thermodynamics, when two objects are kept in contact, heat (energy) is transferred from one to the other until they reach the same temperature (are in thermal equilibrium). When the objects are at the same temperature there is no heat transfer.

So, at equilibrium, $q_{lost}$ = $q_{gain}$ , $q_{lost}= q_{milk}$ + $q_{coffee}$

q=m×c×T, where q = heat energy, m = mass of a substance, c = specific heat (units J/kg∙K), T is temperature

$q_{lost}= (15X13X4.19)+(148X88.3X4.19), (15+148)X4.19XT_{final}$ =(15X13X4.19)+(148X88.3X4.19)

$T_{final}$ = 81.37 ° C

6 0

3 years ago

Please help with this , thanks you guys very much

ahrayia [7]

Answer:

I am giving u some explanation related this question pls see that 

it may help u

Explanation:

The pH scale measures how acidic an object is. Objects that are not very acidic are called basic. The scale has values ranging from zero (the most acidic) to 14 (the most basic). As you can see from the pH scale above, pure water has a pH value of 7. This value is considered neutral—neither acidic or basic. Normal, clean rain has a pH value of between 5.0 and 5.5, which is slightly acidic. However, when rain combines with sulfur dioxide or nitrogen oxides—produced from power plants and automobiles—the rain becomes much more acidic. Typical acid rain has a pH value of 4.0. A decrease in pH values from 5.0 to 4.0 means that the acidity is 10 times greater.

How pH is Measured

There are many high-tech devices that are used to measure pH in laboratories. One easy way that you can measure pH is with a strip of litmus paper. When you touch a strip of litmus paper to something, the paper changes color depending on whether the substance is acidic or basic. If the paper turns red, the substance is acidic, and if it turns blue, the substance is basic

4 0

2 years ago

g All of the molecules below have polar bonds but only one of the molecules is a polar molecule. Which one is a polar molecule?

lbvjy [14]

Answer: $NF_3$

Explanation:

Geometrical symmetry of the molecule and the polarity of the bonds determine the polarity of the molecule.

The molecule that has zero dipole moment that means it is a geometrically symmetric molecule and the molecule which has some net dipole moment means it is a geometrically asymmetric molecule.

As the molecule is symmetric, the dipole moment will be zero as dipole moments cancel each other and the molecule will be non-polar.

As the molecule is asymmetric, the dipole moment will not be zero and the molecule will be polar.

Example: $NF_3$

Thus, we can say that $NF_3$ is a polar molecule.

4 0

2 years ago