If an atom has three shell and number of valence electrons are two. Is this element metal
or non-metal and why? Name the element and it’s valency.

Hey there!:

Density = 30 mg/mL

Mass = 150 mg

Volume = ??

Therefore:

D = m / V

30 = 150 / V

V = 150 / 30

V = 5.0 mL

converts volume into liters :

5.0 mL / 1000 => 0.005 L or 5.0 x 10⁻³ L

Hope this helps!

Answer:

Carbon dioxide extinguishes work by displacing oxygen, or taking away the oxygen element of the fire triangle. The carbon dioxide is also very cold as it comes out of the extinguisher, so it cools the fuel as well.

Answer:

The correct answer is B

Explanation:

This question seeks to test the difference between mass and weight.

Mass is a measurement of the amount of matter present in an object. While weight is a measurement of the force of gravity pulling (the mass of) an object. Hence, measuring the weight of the moon rocks in the moon might be a waste since the weight of the object on earth will produce a different value due to the difference in the force of gravity between the earth and the moon.

Answer:

b

Explanation:

ayo thanks mate :0000000000000000000000

Answer:

5 primary carbon atoms

3 secondary carbon atoms

4 tertiary carbon atoms

6 hydrogen atoms

You can use the scientific method everyday by asking questions and doing experiments. For example, you want to know how a fire starts, so you do an experiment with it!

Answer:

ok dear have a nice day

carry on learing

Answer:

A body becomes weightless in a zero-gravity scenario and when a force is applied to a body that is equal and opposite to the force of gravity. If the body is falling only under the influence of gravity.

Answer:

A body becomes weightless in a zero-gravity scenario and when a force is applied to a body that is equal and opposite to the force of gravity.If the body is falling only under the influence of gravity.

Explanation:

The nitrogen dioxide is a covalent compound where one nitrogen is the central atom which is bonded to two oxygen atoms, where one oxygen atom is bonded by a single bond and other oxygen atom by a double bond.

Answer: colavent

Explanation:

Answer:

Force=mass ×acceleration.

20=10×acceleration.

20=10a.

a=2m/s^2.

the trapped salts go to seawater concentrate

Answer:

a formula giving the proportions of the elements present in a compound but not the actual numbers or arrangement of atoms.

Hope this helped!!!

Answer:

Empirical formulas show the simplest whole-number ratio of atoms in a compound

Explanation:

Answer:

An alcohol with three other carbons attached to the carbon with the hydroxyl group

An alcohol with two other carbons attached to the carbon with the hydroxyl group

Explanation:

If we look at 3-ethyl-3-pentanol, we will discover that the compound is a tertiary alcohol. That is, the carbon atom bearing the hydroxyl group is attached to three other carbon atoms as gown in image 1 attached.

For 2-hexanol, the carbon atom bearing the hydroxyl group is attached to two other carbon atoms hence the alcohol is a secondary alcohol. The compound is shown in image 2 attached.

Answer:

D.) A measure of disorder

Explanation:

I got it correct on founders edtell

Answer:

Diamonds

Explanation:

The melting point of sugar is 186C

The melting point of oxygen is -218C

The melting point of diamonds are 4078C

Therefore diamonds have the highest melting point.

You can also think of their structures, as diamonds have a covalent network structure, meaning they are really strong and have a high melting point

Oxygen has a covalent molecular structure

Sugar has a much weaker covalent network structure

Answer:3.6 x 101 or 8.77 x 10-1

Answer:

an oxygen atom with 8 electrons, 8 protons, and 9 neutrons

Explanation:

A proton has a positive charge and an electron has a negative charge. Magnitude of both of these charges is same. So, we need the same number of electrons and protons to make the atom neutral.

Neutron is neutral, so we can safely ignore it in this question.

Answer:

an oxygen atom with 8 electrons, 8 protons, and 9 neutrons

Explanation:

Answer:

Option D. 4

Explanation:

Ag(s) + NO3–(aq) + H+(aq) → Ag+(aq) + NO(g) + H2O(l)

To know the coefficient of H+, let us balance the equation. This is can be done as shown below:

Ag(s) + NO3–(aq) + 2H+(aq) → Ag+(aq) + NO(g) + H2O(l)

There are 3 atoms of O on the left side and a total of 2 atoms on the right side. It can be balance by putting 2 in front of H2O as shown below:

Ag(s) + NO3–(aq) + H+(aq) → Ag+(aq) + NO(g) + 2H2O(l)

There are 4 atoms of H on the right side and 1 atom on the left side. It can be balance by putting 4 in front of H+ as shown below:

Ag(s) + NO3–(aq) + 4H+(aq) → Ag+(aq) + NO(g) + 2H2O(l)

Total charge on the left side:

– 1 + 4 = +3

Total charge on the right side:

+1

To balance the charge, we simply put 3 in front of Ag and Ag+ as shown below:

3Ag(s) + NO3–(aq) + 4H+(aq) → 3Ag+(aq) + NO(g) + 2H2O(l)

Now the equation is balanced.

The coefficient of H+ is 4.

Answer:

The correct answer is 15.54 kJ per degree C.

Explanation:

The enthalpy change for one mole of a substance, which combines or burns with the oxygen under the standard conditions, that is, at 25 degree C and 1 bar pressure is known as the standard molar enthalpy of combustion. The amount of heat transferred can be calculated by using the formula, q = mcΔT -------------(i)

Here q is the amount of heat transferred, c is the specific heat, ΔT is the change in temperature, and m is the mass of the substance. As in case of bomb calorimeter, mass if considered constant, thus, for calorimeter the equation mentioned will become, q = cΔT ---- (ii)

The standard molar enthalpy of combustion for carbon is -393.5 kJ/mol, that is, -393.5 kJ per mole of heat is generated by burning one mole of carbon. The molecular mass of carbon is 12 gram per mole.  

Thus, the number of moles of carbon equivalent to 0.562 grams of carbon can be determined as,  

Number of moles of carbon = mass / molecular mas

= 0.562 grams / 12 gram per mole

= 0.047 mol

The heat generated by burning 0.562 grams or 0.047 mole will be,  

q = ΔH° × number of moles

= (-393.51 kJ/mol) × 0.047 mol

= -18.49 kJ, the negative sign shows that the heat is produced.  

To find heat capacity of calorimeter, put the value of q as -18.49 kJ, for ΔT as (27.93 °C - 26.74 °C) in the equation (ii)

18.49 kJ = c × (27.93 - 26.74)

c = 18.49 kJ/1.19 °C

c = 15.54 kJ/°C

Answer:

It form new chemical from chemical reaction

Answer:

Product

Explanation:

Answer:

[tex]\large \boxed{350}[/tex]

Explanation:

In multiplication and division problems, the answer can have no more significant figures than the number with the fewest significant figures.

My calculator gives the result:

[tex]\dfrac{4568}{13} = 351.3846154[/tex]

4658 has four significant figures.

     13 has two significant figures.

You must round to two significant figures.

That is, you drop all the digits to the right of the 5 — the red line in Fig. 1 below. You are rounding to the nearest ten.

To round a number to the nearest ten, you look at the number in the ones place (1). See Fig. 2.

If the number to be dropped — the digit in the ones place — is less than 5, you drop the digit in the ones place (Fig. 3). It becomes a zero.

The number in the tens place is a trailing zero. It is not significant.

[tex]\text{The quotient of $\dfrac{4658}{13}$ is $\large \boxed{\mathbf{350}}$}[/tex]

Answer:

Explanation:

Hello friend

The answer is Churning.

Hope this helps

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Answer:

Anna didn't wear a lab coat

Explanation:

The first thing anyone who is to carry out a procedure or an experiment in a lab needs to do when he/she enters a lab is to wear a lab coat. This is a lab safety rule that protects the individual from been affected by spillage that could occur as a result of the experiment been conducted.

From the narration in the question, it is not stated anywhere that Anna wore a lab coat before embarking on her lab procedure.

Answer:

C, wear goggles, anytime chemicals, heat, or glassware are used.

Explanation:

This is the correct answer on the Lincoln learning platform.

Answer:

Heat = 3138J

Explanation:

In the system, the sample of Copper is releasing heat that produce the increasing in the temperature of water.

Using the equation of calorimeter, we can find the heat released for the sample of copper (The same that is absorbed for the water):

Q = C×m×ΔT

Where Q is heat, C is specific heat (For water: 4.184J/molK), m is the mass of water (50g) and ΔT is change in temperature of water (40°C-25°C = 15°C)

Replacing:

Q = 4.184J/molK×50g×15°C

Q = 3138J is the heat released for the sample of Copper (The same absorbed for the water).

Answer:

heat=3138j

Explanation:

In the system, the sample of Copper is releasing heat that produce the increasing in the temperature of water.

Using the equation of calorimeter, we can find the heat released for the sample of copper (The same that is absorbed for the water):

Q = C×m×ΔT

Where Q is heat, C is specific heat (For water: 4.184J/molK), m is the mass of water (50g) and ΔT is change in temperature of water (40°C-25°C = 15°C)

Replacing:

Q = 4.184J/molK×50g×15°C

Q = 3138J is the heat released for the sample of Copper (The same absorbed for the water).

Answer:

B. Oxygen

Explanation:

Basically count each arrow since each arrow represents an electron. Then use the periodic table to find the element with 8 electrons, which is oxygen. Also, if you know the orbital patterns, you can identify that the 2p orbital represents an element in Group 16.

Answer:

a 1) XZ2

2) YZ

3) X2

b 1) Ionic bond

2) Ionic bond

3) covalent bond

c) ionic compounds has high melting and boiling point

ionic compounds can conduct electicity in aqueous form

covalent compounds have electrons shared between the atoms

covalent compounds have lower melting point compared to ionic compound

Answer:

(i) XZ = Potassium Sulfide [K2SO4]

(ii) YZ = Potassium Chloride [KCI]

(iii) X = Sulfur [S]

b) (i) Ionic Bond. (ii) Ionic Bond. (iii) Covalent Bond.

c) (i) Ionic compounds have high melting and boiling points.

(ii) Ionic compounds can conduct electricity in a molten state or a solution as they have ions that can move and carry charge.

(iii) Covalent compounds have low melting and boiling points.

(iv) Covalent compounds can not conduct electricity as all electrons are involved in bonding so there are no free electrons or ions to carry the charge.

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Answer:

0.571moles

Explanation:

The Avogrado's number or constant denoted by NA will be used for this question.

The Avogrado's number = 6.022 × 10^23 particles, is contained in 1 mole of a substance.

To get the number of atom/particles in a substance, the formula: N= n × NA is used.

Where; N= Number of atoms in

substance

n= number of moles

NA= Avogadro's constant

Hence, to find the number of moles of copper equivalent to 3.44 × 10^23, we say: n= N / NA

That is, n = 3.44 × 10^23 / 6.022 × 10^23

= 0.5712

Therefore, 0.571 moles of Copper (Cu) is equivalent to 3.44 × 10^23 atoms of Copper.