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3 years ago

What element has 7 valence electrons and 4 electron shells

Chemistry

1 answer:

Dmitry [639]3 years ago

4 0

Answer:

Explanation: 4th shell so 4th row and count 7 from the left most column

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How many moles of oxygen are produced when 5.12 moles of magnesium chlorate decomposes into magnesium chloride and oxygen?

goldenfox [79]

The moles of oxygen produced is calculated as follows

write a balanced reacting equation, that is

Mg(ClO3)2 ---->MgCl2 + 3O2

from the equation above the reacting ratio of Mg(ClO3)2 to O2 is 1: 3 therefore the moles of O2 produced = 5.12 moles x3 =15.36 moles

4 0

3 years ago

Which of the following describes a chemical property of a metal?

julia-pushkina [17]

Answer:

Reacts with acid

Explanation:

Study Island

8 0

3 years ago

Read 2 more answers

An iron nail rusts when exposed to oxygen. According to the following reaction, how many grams of iron(III) oxide will be formed

-Dominant- [34]

Answer:

53.2

Explanation:

The balanced reaction is:

2Fe(s) + 3O₂(g) → Fe₂O₃

It means that 3 moles of oxygen form 1 mol of iron(III) oxide. The molar masses are: Fe = 55.8 g/mol and O = 16 g/mol. So

O₂ = 2x 16 = 32 g/mol

Fe₂O₃ = 2x55.8 + 3x16 = 159.6 g/mol

So, 32 g of O₂ corresponds to 1 mol of O₂. The stoichiometry calculus must be (always in moles):

3 mol of O₂ ------------------------ 1 mol of Fe₂O₃

1 mol of O₂ ------------------------ x

By a direct simple three rule:

3x = 1

x = 1/3 mol of Fe₂O₃

The mass is the molar mass multiplied by the number of moles, so:

m = 159.6x (1/3)

m = 53.2 g iron (III) oxide.

6 0

3 years ago

Explain why NO is more soluble in water than either N2 or O2. Fill in the following blanks.

jek_recluse [69]

Answer:

a. Larger molecular size

b. Ability to react with water

c. Polarity

d. Shorter bond length

Explanation:

Ethene is a larger molecule than oxygen and nitrogen hence it is more soluble than the both other gases .

SO2 dissolves readily in water to yield an acid solution. It is an acid anhydride.

Nitric oxide is a polar compound. It remains very much polar while nitrogen and oxygen are non polar.

Nitrogen is sp hybrized, this leads to a very short bond and does not easily interact with oxygen and nitrogen

3 0

3 years ago

a calorimeter contained 75.0 g of water at 16.95 C. A 93.3-g sample of iron at 65.58 C was placed in it, giving a final temperat

Nostrana [21]

Answer:- $\frac{382.69J}{0C}$ .

Solution:- Mass of Iron added to water is 93.3 g. Initial temperature of iron metal is 65.58 degree C and final temperature of the system is 19.68 degree C.

temperature change, $\Delta T$ for iron metal = 65.58 - 19.68 = 45.9 degree C

specific heat for the metal is given as 0.444 J per g per degree C.

let's calculate the heat lost by iron metal using the equation:

$q=mc\Delta T$

where, q is the heat energy, m is mass, c is specific heat and delta T is change in temperature. let's plug in the values and calculate q for iron metal:

$q=93.3g(45.9^0C)(\frac{0.444J}{g.^0C})$