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3 years ago

Plz answer question 9 in the picture... with an explanation

Chemistry

2 answers:

LenaWriter [7]3 years ago

5 0

Answer:

Figure B show element

Explanation:

Element is made up of same type of atoms and in figure b only one type of atom is present

pashok25 [27]3 years ago

3 0

Answer:

Explanation:

A substance that cannot be broken down into simpler substances by chemical means. An element is composed of atoms that have the same atomic number, that is, each atom has the same number of protons in its nucleus as all other atoms of that element.

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Answer:

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3 years ago

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Vadim26 [7]

Answer:

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8 0

3 years ago

What is the amount of energy for a photon that has a 125 cm wavelength

Lera25 [3.4K]

Answer:

1.59 x 10⁻²⁵ J.

Explanation:

The energy of a photon is calculated Planck - Einstein's equation:

E = h ν , where

E is the energy of the photon,

h is Planck's constant <em>(h = 6.626 x 10 ⁻³⁴ J.s)</em>

ν is the frequency of the photon

There is a relation between the frequency (ν ) and wave length (λ).

λ.ν = c,

where c is the speed of light in vacuum (c = 3 .0 x 10 ⁸ m/s).

λ = 125 cm = 1.25 m.

<em>Now, E = h.c/λ.</em>

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3 years ago

C. If 62.9 g of lead (II) chloride is produced, how many grams of lead (II) nitrate were

melomori [17]

Answer:

Mass = 76.176 g

Explanation:

Given data:

Mass of lead(II) chloride produced = 62.9 g

Mass of lead(II) nitrate used = ?

Solution:

Chemical equation:

Pb(NO₃)₂ + 2HCl → PbCl₂ + 2HNO₃

Number of moles of lead(II) chloride:

Number of moles = mass/molar mass

Number of moles = 62.9 g/ 278.1 g/mol

Number of moles = 0.23 mol

Now we will compare the moles of lead(II) chloride with Pb(NO₃)₂ from balance chemical equation:

PbCl₂ : Pb(NO₃)₂

1 : 1

0.23 : 0.23

Mass of Pb(NO₃)₂:

Mass = number of moles × molar mass

Mass = 0.23 mol × 331.2 g/mol

Mass = 76.176 g

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4 years ago

Please help me with this homework

ella [17]

Answer:

Density is the correct answer choice.

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3 years ago

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