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3 years ago

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Chemistry

1 answer:

Jet001 [13]3 years ago

6 0

Answer:

Explanation:

The formation of ion occurs when an atom that is said to be neutral gains or losses electrons.

At the time it gains electrons, it is regarded that a negative ion (anion) is formed.

When it loses electron, it is regarded that a positive ion (cation) is formed.

Atomic number = No of protons and electrons occurring in a neutral atom.

Given that:

Protons = 14

electron = 18

Net Charge = no of proton - no of electron

= 14 - 18

= -4

Mass number = 14 + 15 = 29

So, the chemical symbol = $Si^{-4}$

For ion with

27 proton, 32 neutrons and 25 electrons

Net charge = 27 - 25

= +2

Mass number = 27 + 32 = 59

Thus, the chemical symbol = $Co^{+2}$

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In your own words describe the difference between the movement of particles in liquids and the movement of particles in gases.

xxMikexx [17]

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3 years ago

What is the percent composition of carbon in heptane, C7H16?

JulsSmile [24]

Answer:

Option d, 84%

Explanation:

1) Determine the molar mass of the heptane

element # of atoms atomic mass total mass

C 7 12.011 g/mol 7×12.011 g/mol = 84.077 g/mol

H 16 1.008 g/mol 16×1.008 g/mol = 16.128 g/mol

-------------------

Molar mass = 100.205 g/mol

2) Percent of carbon, %

% = (mass of element / molar mass )×100

= (84.077 g/mol / 100.205 g/mol )×100 = 83.83 %

Round to two significant figures: 84% ← answer

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3 years ago

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Lady_Fox [76]

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Explanation:

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3 years ago

Pb(NO3)2 how do i solve this

Sindrei [870]

You can see the periodic table one by one.

Pb(NO3)2 = PbN2O6

So there are

1Pb

and so you find the molecular mass from the periodic table and add all the numbers

Molacular mass of

Pb = 207

N = 14

O = 16

multiply it with the number of atoms

1Pb = 207 × 1 = 207

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Molecular mass total = 207 + 28 + 96 = 331

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3 years ago

Ammonium perchlorate is the solid rocket fuel used by the U.S. Space Shuttle. It reacts with itself to produce nitrogen gas , ch

SpyIntel [72]

Answer:

2.94 g of water are produced by this decomposition

Explanation:

We need to determine the reaction to solve this problem:

The reactant is the ammonium perchlorate

The products are N₂, Cl₂, O₂ and H₂O

The reaction is: 2NH₄ClO₄ → N₂ + Cl₂ + 2O₂ + 4H₂O

We convert the mass of the reactant to moles:

9.6 g . 1 mol / 117.45 g = 0.0817 moles

Ratio is 2:4. Let's make a rule of three:

2 moles of perchlorate produce 4 moles of water.

Then, 0.0817 moles of perchlorate will produce (0.0817 . 4)/2 = 0.163 moles

We convert the moles of produced water, to mass (g)

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8 0

3 years ago