Need some help please answer please

Answer:

C. LiF, CaCl2, MgO

Explanation:

Ionic compound: It is that compound which consist of negative and position ions and held together by electrostatic force of attraction.

The ionic compound is neutral.

The ionic compound formed between metal and non-metal.

Covalent compound: It is that compound in which sharing of electrons between two atoms occur.

A.[tex]CaCl_2,H_2O,LiF[/tex]

H2O is not ionic compound. It is polar covalent.

Therefore, it does not contain only ionic compounds.

B.CO2,K2O,P4O10

CO2 and P4O10 are not ionic .It is covalent.

Therefore, it does not contain only ionic compounds.

C. LiF,CaCl2 ,MgO

All compounds are ionic because in given compounds one ion is negative  and one is metal (positive).

Therefore, it contains only ionic compounds.

D.NO2,MgO,CuCl2

NO2 is not ionic.

Therefore, it does not contain only ionic compounds.

Option C is correct.

Answer:

The number of O₂ molecules that are left in the cylinder is 1.70x10²⁴.

Explanation:

The number of oxygen molecules can be found using the Ideal Gas law:

[tex] PV = nRT [/tex]        

Where:

P: is the pressure = 100 psi

V: is the volume = 10 L

n: is the number of moles =?

T: is the temperature = 20 °C = 293 K

R: is the gas constant = 0.082 L*atm/(K*mol)

Hence, the number of moles is:

[tex]n = \frac{PV}{RT} = \frac{100 psi*\frac{1 atm}{14.7 psi}*10 L}{0.082 L*atm/(K*mol)*293 K} = 2.83 moles[/tex]

Now, the number of molecules can be found with Avogadro's number:

[tex]n_{m} = \frac{6.022 \cdot 10^{23}\: molecules}{1\: mol}*2.83 moles = 1.70 \cdot 10^{24} \: molecules[/tex]

Therefore, the number of O₂ molecules that are left in the cylinder is 1.70x10²⁴.

I hope it helps you!              

Answer:

Explanation: You're welcome ✓

Answer:

the location of the center of gravity for the entire body is 1.08 m

Explanation:

Given the data in the question;

w1 = 458 N, y1 = 1.34 m

w2 = 120 N, y2 = 0.766 m

w3 = 89.8 N, y2 = 0.204 m

The location arrangement of the body part is vertical, locate the overall centre of gravity by simply replacing the horizontal position x by the vertical position y as measured relative to the floor.

so,

[tex]Y_{centre of gravity}[/tex] = (w1y1 + w2y2 + w3y3 ) / ( w1 + w2 + w3 )

so we substitute in our values

[tex]Y_{centre of gravity}[/tex] = (458×1.34 + 120×0.766 + 89.8×0.204 ) / ( 458 + 120 + 89.8 )

[tex]Y_{centre of gravity}[/tex] = 723.9592 / 667.8

[tex]Y_{centre of gravity}[/tex] = 1.08 m

Therefore, the location of the center of gravity for the entire body is 1.08 m

Answer:

1. ELE to KE = Electrical energy conversion to kinetic energy.

2. KE to ELE = kinetic energy conversion to electrical energy.

3. CE to ELE = chemical energy conversion to electrical energy.

Explanation:

The Law of Conservation of Energy states that energy cannot be destroyed but can only be transformed or converted from one form to another.

Some examples of energy are chemical energy, electrical energy, kinetic energy, sound energy, potential energy, light energy, etc.

The transformation of energy from one form to another are described below;

1. A hair dryer plugged into the wall: it involves the conversion of electrical energy to kinetic energy. The energy type present in the wall socket is electrical energy which powers the hair dryer to have kinetic energy i.e the energy possessed due to motion of hair dryer.

2. A hand crank generator emergency radio: it illustrates the conversion of kinetic energy to electrical energy. The hand crank generator possess kinetic energy as it is being wounded before it is then converted into electrical energy which powers the radio.

3. A battery operated fan: it illustrates the conversion of chemical energy to electrical energy. The cells present in battery possess chemical energy that is being converted into electrical energy to power the fan.

Answer:

mass and distance

Explanation:

mass, and distance. The force of gravity depends directly upon the masses of the two objects, and inversely on the square of the distance between them.

Answer:

The answer is "[tex]2.352 \ \frac{m}{s}[/tex]"

Explanation:

[tex]\to mass(m_1)=102 \ kg\\\\\to mass(m_2)=10 \ kg \\\\\to v=2.10\ \frac{m}{s}\\\\[/tex]

momentum before:

[tex]\to p=(m_1+m_2)v[/tex]

       [tex]=(102+10)2.10\\\\=(102\times 2.10 +10 \times 2.10)\\\\=214.2+21\\\\=235.2[/tex]

momentum After:

[tex]\to p=(m_1+m_2)v[/tex]

       [tex]=(102\times 0 +10 \times v)\\\\ =(0 +10v)\\\\=10v\\[/tex]

Calculating the conservation of momentum:

[tex]\to \text{momentum before = momentum After}[/tex]

[tex]\to 235.2=10v\\\\\to v= \frac{235.2}{10}\\\\ \to v=2.352 \ \frac{m}{s}[/tex]