What is the percent composition of sodium (na) in baking soda

Pls HELP!!!! Why does copper oxide appear on a penny faster when a penny is heated in a flame than when the penny is at room tem

balu736 [363]

The rate of reaction between oxygen and copper is higher at high temperature. The rate of reaction between oxygen and copper is lower at room temperature.

at high temperature copper penny will react with oxygen as shown below

$2Cu(s)+O_{2}-->2CuO$

The reaction does not occur easily at room temperature

We can say that the reaction between copper and oxygen is an endothermic reaction so the rate of reaction is high at high temperature.

The bond energy of oxygen molecules need energy to react with copper and form copper oxide.

5 0

3 years ago

0.456 grams of a monoprotic acid is titrated with 45.88 mL of 0.0500 M NaOH. What is the molecular mass (molar mass) of the acid

aivan3 [116]

Answer:

$Molar\ mass= 198.78\ g/mol$

Explanation:

Considering:

$Molarity=\frac{Moles\ of\ solute}{Volume\ of\ the\ solution}$

$Moles =Molarity \times {Volume\ of\ the\ solution}$

Given :

For NaOH :

Molarity = 0.0500 M

Volume = 45.88 mL

The conversion of mL to L is shown below:

1 mL = 10⁻³ L

Thus, volume = 45.88×10⁻³ L

$Moles_{NaOH} =0.0500 \times {45.88\times 10^{-3}}\ moles=0.002294\ moles$

Moles of NaOH = Moles of monoprotic acid

So, moles of monoprotic acid = 0.002294 moles

Given that:- mass = 0.456 g

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$0.002294\ moles= \frac{0.456\ g}{Molar\ mass}$

$Molar\ mass= 198.78\ g/mol$

3 0

3 years ago

Can someone plzzz help me with this numbers 1-13 plzz show work plzzz due tomorrow I need help I’ll give brainliest

ipn [44]

Explanation:

Question 1:

We have to use the aid of the periodic table to solve this problem and decipher some of the species.

The number of protons is the number of positively charged particles. It the same as the atomic number.

Number of electrons is the number of negatively charged particles.

Neutrons do not carry any charges.

Mass number = number of protons + number of neutrons

Solving:

Symbol #atomic #protons #electrons #neutrons mass# atomic mass

Fe 26 26 26 30 56 55.8

As³⁺ 33 33 36 42 75 74.9

Ag 47 47 47 61 108 107.9

I¹⁻ 53 53 54 74 127 126.9

K 19 19 19 20 39 39.1

learn more:

Atomic number brainly.com/question/2057656

Question 2:

An ion is an atom that has either lost or gained electron.

A positively charged ion is one that has lost electrons and the number of protons is now more. They are called cation

A negatively charged specie is one that has gained electrons and the number of electrons are now more. They are called anions.

Mass number is the superscript = Number of protons + number of neutrons

Atomic number = number of protons = number of electrons for neutral atoms

Species:

₇¹⁴N³⁻

Number of protons = 7

Number of electrons = 7 + charge = 7+ 3 = 10

Number of neutrons = 14 - 7 = 7

¹¹²₄₈Cd²⁺

Number of protons = 48

Number of electrons = 48 -2 = 46

Number of neutrons = 112 - 48 = 64

⁶⁴₂₉Cu

Number of protons = 29

Number of electrons = 29

Number of neutrons = 64 - 29 = 35

¹¹⁹₄₄Sn⁴⁺

Number of protons = 44

Number of electrons = 44 - 4 = 40

Number of neutrons = 119 - 44 = 75

¹⁹₉F⁻

Number of protons = 9

Number of electrons = 9+ 1 = 10

Number of neutrons = 19 - 9 = 10

learn more:

Number of protons, neutrons and electrons brainly.com/question/2757829

Question 3:

Mass number

The number 79 in Se - 79 specifies the mass number of the element. It suggests that Se is the number 34 element on the periodic table.

The periodic table arranges elements based on their atomic number.
The atomic number is the number of protons in an atom
Every atoms has a unique atomic number which makes them different from other atoms.
In neutral atoms, the atomic number is the same as the number of protons and the number of electrons in an atom.
The mass number is the number of protons plus neutrons of an atom.

learn more:

Mass of proton brainly.com/question/4999318

Question 4:

Number of protons = 14

Atomic structure:

²⁸₁₄Si

In this atom designated above Si is the symbol of Silicon, the fourteenth element in the periodic table.
The superscript 28 is the mass number of the atom
The mass number is the number of protons and neutrons in the nucleus of the atom.
It is also called the nucleon number because protons and neutrons are nucleons.
The subscript 14 is the atomic number.
It is the number of protons in the atom.
For neutral atoms, it is also the number of electrons

learn more:

Number of protons, neutrons and electrons brainly.com/question/2757829

Question 5:

The total number of subatomic particles = 289

Structure is ²⁰⁷₈₂Pb

The subatomic particles in an atom are protons, neutrons and electrons
Protons are the positively charged particles in an atom
Neutrons have no charge
Electrons carry negative charges

In the atom above, since it is neutral, the number of protons = number of electrons

Number of protons = atomic number

This is the subscript;

Number of protons = 82

Number of electrons = 82

Number of neutrons = mass number - atomic number

Mass number is the superscript

Number of neutrons = 207 - 82 = 125

The total number of subatomic particles = number of protons + number of neutrons + number of electrons

Total number of subatomic particles = 82 + 82 + 125 = 289

learn more:

protons, neutrons and electrons brainly.com/question/2757829

Question 6:

29

Given parameters :

Number of neutrons = 31

Mass number = 59

Unknown:

Atomic number = ?

Solution:

The mass number of an atom is the number of protons and neutrons it contains.

The mass of an atom is concentrated in the nucleus and this is where we derive the mass number from;

Mass number = number of protons + number of neutrons

Number of protons = 59 - 31 = 28

The number of protons in an atom is the same as the atomic number.

Atomic number = 28

learn more:

Atomic number brainly.com/question/2057656

Question 13 remainder;

When sodium loses an electron, the number of protons will be more than that of electrons

It then becomes an ion;

Number of protons = 11

Number of electrons = 11 - 1 = 10 Charge = 11 - 10 = 1+

With a loss of one electron, sodium will now resemble Ne more closely because it has a stable configuration.

learn more

lon brainly.com/question/4670413

#learnwithBrainly

7 0

3 years ago

When 2 grams of powdered lead (IV) oxide was added to 100 cm3 of hydrogen peroxide, water and oxygen were produced. Lead (IV) ox

kirza4 [7]

Answer:

The right answer is:

Replacing the powdered lead oxide with its large crystals

Removing lead (IV) oxide from the reaction mixture

Using 1.0 gram of lead (IV) oxide

Explanation:

Based on the given information this reaction is the catalytic decomposition of H₂O₂ into water and oxygen using Lead (IV) oxide as a catalyst.

The catalyst surface area is directly proportional to the reaction rate

So, Replacing the powdered lead oxide with its large crystals would decrease the reaction rate due to the has larger surface area than its large crystals.

2. Also, Removing lead (IV) oxide from the reaction mixture the reaction rate decreased because as the catalyst is removed.

3. Using 50 cm³ of hydrogen peroxide doesn't affect the rate because the concentration of the reactant doesn't change.

4. Using 1.0 gram of lead (IV) oxide would decrease the reaction rate because the amount of catalyst decreased

So, The right answer is:

Replacing the powdered lead oxide with its large crystals

Removing lead (IV) oxide from the reaction mixture

Using 1.0 gram of lead (IV) oxide

7 0

4 years ago

Which statement summarizes the difference between mass and weight?

alexgriva [62]

Answer:

Mass is the amount of matter in an object.

Weight is how much an object weighs.

Hope this helps!

6 0

3 years ago