Milk Souring a Chemical Change b Physical Change

Which substance has a molar mass of 33.99 g/mol?

alex41 [277]

Answer:

PH₃.

Explanation:

Hello.

In this case, among the options:

PH₃, GaF₃, SF₂ and CO₂

We compute their molar masses by adding the atomic masses of the constituting elements by their subscripts:

$M_{PH_3}=m_P+3*m_H=30.97+3*1.01=34.00g/mol\\\\M_{GaF_3}=m_{Ga}+3*m_F=69.72+3*19.00=126.72g/mol\\\\M_{SF_2}=m_{S}+2*m_F=32.07+2*19.00=70.07g/mol\\\\M_{CO_2}=m_{C}+2*m_O=12.01+2*16.00=44.01g/mol$

Thus, the answer is PH₃.

Best regards.

6 0

3 years ago

The chemical equation of the reaction between Hydrogen and Oxygen is given below

Firdavs [7]

Answer:

1. a. The reactants are H₂ and O₂; The product is H₂O

b. The equation is not balanced because the number of atoms of the elements reacting is not equal to the number of atoms produced. 2 atoms of oxygen reacted but only one atom of oxygen is produced.

c. 2 H₂ + O₂ ---> 2 H₂O

2. a. The monotonic molecule is the sodium molecule, Na, since itnis made up of only one atom in its molecule.

The diatomic molecule is oxygen molecule, O₂, since it is made up of two atoms in its molecule.

b. The chemical compound present is sodium oxide, Na₂O

c. 4 Na + O₂ ---> 2 Na₂O

Explanation:

In a chemical reaction, the reactants are the elements or compounds which are converted to a new substance whichnis known as the product. The products are the new substances formed from the reactants.

In the given equation of reaction below;

H₂ + O₂ ---> H₂O

a. The reactants are H₂ and O₂; The product is H₂O

b. The equation is not balanced because the number of atoms of the elements reacting is not equal to the number of atoms produced. 2 atoms of oxygen reacted but only one atom of oxygen is produced.

c. 2 H₂ + O₂ ---> 2 H₂O

2. Given the reaction equation below:

Na + O₂ ---> Na₂O

a. The monotonic molecule is the sodium molecule, Na, since it is made up of only one atom in its molecule.

The diatomic molecule is oxygen molecule, O₂, since it is made up of two atoms in its molecule.

b. The chemical compound present is sodium oxide, Na₂O since itconsists of two chemically combined elements, sodium and oxygen.

c. 4 Na + O₂ ---> 2 Na₂O

6 0

3 years ago

There are two isotopes of boron: boron-10 and boron-11. Explain, in terms of weighted average atomic mass, the difference in per

Zolol [24]

Answer:

Percent abundance of B¹⁰ is 19.9% and B¹¹ is 80.1%.

The weighted average atomic mass of boron is 10.811 amu.

Explanation:

We know that average atomic mass of Boron is 10.811 amu and there are two isotopes of boron B¹⁰ (10.012938) and B¹¹ (11.009305)

We will determine the percent abundance of each isotopes.

First of all we will set the fraction for both isotopes B¹⁰ and B¹¹.

X for the isotopes having mass 11.009305 amu.

1-x for isotopes having mass 10.012938 amu.

The average atomic mass of Boron is 10.811 amu

we will use the following equation,

11.009305x + 10.012938 ( 10.012938 -x) = 10.811

11.009305x + 10.012938 - 10.012938 x = 10.811

11.009305x - 10.012938 x = 10.811 - 10.012938

0.996367x = 0.798062

x= 0.798062 / 0.996367

x= 0.800972

Percent abundance of B¹¹.

0.800972 × 100 = 80.1 %

80.1 % is abundance of B¹¹ because we solve the fraction x.

now we will calculate the abundance of B¹⁰.

(1-x)

1-0.800972 =0.199

Percent abundance of B¹⁰.

0.199 × 100= 19.9%

19.9% for B¹⁰.

Now we can calculate the average atomic mass of boron.

Formula:

Average atomic mass = [mass of isotope× its abundance] + [mass of isotope× its abundance] +...[ ] / 100

Now we will put the values in formula.

Average atomic mass = [19.9 × 10.012938] + [80.1 × 11.009305] / 100

Average atomic mass = 199.2575 + 881.8453 / 100

Average atomic mass = 10.811 amu

8 0

3 years ago

In atomic solids where the lattice points are occupied by Group 8 ( 18) atoms, the atoms are held together by __________ forces.

shtirl [24]

Answer:

London dispersion forces

Explanation:

There are different forces of attraction that helps to hold atoms or Molecules of a particular substance together. Some of the forces of attraction are ionic/ electrovalent bond, covalent bond, vander waals forces of attraction and so on.

Under the vander waals forces of attraction we have what is known as the London dispersion forces. This force of attraction is a very weak and it is commonly found in the atoms of noble gases.

The intermolecular force of attraction in which we are talking about that is london dispersion forces is formed as a result of the formation of non-polar dipoles which are not permanent.

8 0

3 years ago

Two 0.75 Amp loads are connected in parallel with a 2500 Milliamperehour Ni-Cd battery. Approximately how long can the battery p

nikdorinn [45]

Explanation:

It is given that two loads have 0.75 Ampere current each. And, they contain 2500 milli ampere per hour Ni-Cd battery.

As both the loads are connected in parallel. Hence, total current will be calculated as follows.

I = $I_{1} + I_{2}$