____ is a gemstone used in clocks and watches.

Calculate the number of moles of each compound, given the number of molecules.

brilliants [131]

Answer:

1. $2.46\times 10^{21}$ molecules of CO₂

2. 10⁴ molecules of H₂O

3. 8.75×10³² molecules of C₆H₁₂O₆

Explanation:

1. $2.46\times 10^{21}$ molecules of CO₂

2. 10⁴ molecules of H₂O

3. 8.75×10³² molecules of C₆H₁₂O₆

5 0

3 years ago

Compare the chemical reactivity of chlorine and bromine. Explain your answer. Thanks in advance

shepuryov [24]

Bromine vs Chlorine | Br vs Cl

Halogens are group VII elements in the periodic table, and all are electronegative elements and have the capability to produce -1 anions.

Bromine

Bromine is denoted by the symbol Br. This is in the 4th period of the periodic table between chlorine and iodine halogens. Its electronic configuration is [Ar] 4s2 3d10 4p5. The atomic number of bromine is 35. Its atomic mass is 79.904. Bromine staChlorine is an element in the periodic table which is denoted by Cl. It is a halogen (17th group) in the 3rd period of the periodic table. The atomic number of chlorine is 17; thus, it has seventeen protons and seventeen electrons. Its electron configuration is written as 1s2 2s2 2p6 3s2 3p5. Since the p sub level should have 6 electrons to obtain the Argon, noble gas electron configuration, chlorine has the ability to attract an electron. ys as a red-brown color liquid at room temperature.

8 0

3 years ago

Natural gas is stored in a spherical tank at a temperature of 13°C. At a given initial time, the pressure in the tank is 117 kPa

drek231 [11]

Answer:

1. the absolute pressure in the tank before filling = 217 kPa

2. the absolute pressure in the tank after filling = 312 kPa

3. the ratio of the mass after filling M2 to that before filling M1 = 1.44

The correct relation is option c ( $\frac{M_{2} }{M_{1} } = \frac{P_{2} T_{1} }{P_{1} T_{2} }$ )

Explanation:

To find -

1. What is the absolute pressure in the tank before filling?

2. What is the absolute pressure in the tank after filling?

3. What is the ratio of the mass after filling M2 to that before filling M1 for this situation?

As we know that ,

Absolute pressure = Atmospheric pressure + Gage pressure

So,

Before filling the tank :

Given - Atmospheric pressure = 100 kPa , Gage pressure = 117 kPa

⇒Absolute pressure ( p1 ) = 100 + 117 = 217 kPa

Now,

After filling the tank :

Given - Atmospheric pressure = 100 kPa , Gage pressure = 212 kPa

⇒Absolute pressure (p2) = 100 + 212= 312 kPa

Now,

As given, volume is the same before and after filling,

i.e. $V_{1}$ = $V_{2}$

As we know that, P ∝ M

⇒ $\frac{p_{1} }{p_{2} } = \frac{m_{1} }{m_{2} }$

⇒ $\frac{m_{2} }{m_{1} } = \frac{p_{2} }{p_{1} }$

⇒ $\frac{m_{2} }{m_{1} } = \frac{312 }{217 } = 1.4378$ ≈ 1.44

Now, as we know that PV = nRT

As V is constant

⇒ P ∝ MT

⇒ $\frac{P}{T}$ ∝ M

⇒ $\frac{M_{2} }{M_{1} } = \frac{P_{2} T_{1} }{P_{1} T_{2} }$

So, The correct relation is c option.

6 0

3 years ago

Elements occur in a number of isotopic forms. In this problem, you will learn about the notation used to distinguish different i

alina1380 [7]

Answer:

Number of protons, Z = 14
Number of neutrons, N = 14

Explanation:

1) About isotopes:

Isotopes are different kind of atoms of the same element. Hence, they have the atomic number (Z), which is the number of protons, the same number of electrons (talking about to neutral atoms, not ions), and different number of neutrons N).

This is, it is the number of neutrons what distinguish different isotopes of an element.

2) About the notation used to distinguish different isotopes:

A superscript and a subscript, both to the left of the chemical symbol of the element, are used to distinguish different isotopes:

A ←------------- This superscript tells the mass number of the isotope

X ←--------- This is the chemical symbol of the element

Z ←-------------- This subscript is the atomic number of isotope

In our case, the notiation for the isotope of silicon is: ²⁸₁₄ Si

So, we have:

28 is the mass number (A)
14 is the atomic number (Z)
Si is the chemical symbol.

Now, you can answer the questions of the part A:

Number of protons: Z = 14

Number of neutrons N:

mass number = number of protons + number of neutrons

A = Z + N

⇒ N = A - Z = 28 - 14 = 14

In conclusion:

Number of protons, Z = 14
Number of neutrons, N = 14

5 0

3 years ago

Pls help me ASAP thank you!!

Stolb23 [73]

Sorry i cant even read that

7 0

3 years ago