GCSE Chemistry - Atoms & Ions #1

Summary

This educational video script delves into the fundamental building blocks of matter: atoms. It explains that atoms consist of a nucleus with protons and neutrons, surrounded by orbiting electrons. Protons carry a positive charge, neutrons are neutral, and electrons have a negative charge. The video clarifies the atomic structure, the relative masses and charges of subatomic particles, and how atoms can become ions by gaining or losing electrons. It also introduces the periodic table, explaining atomic numbers and mass numbers, and their significance in identifying elements.

Takeaways

• 🌌 Everything, whether living or non-living, is composed of tiny particles called atoms.
• 🔬 Atoms consist of a central nucleus and electrons that orbit around the nucleus in shells.
• 🚀 The nucleus is made up of protons and neutrons, which have the same mass and are tightly packed together.
• ⚡ Protons have a positive charge, neutrons are neutral, and electrons have a negative charge.
• ⚖️ The relative mass of protons and neutrons is one, while electrons are much lighter, often considered negligible.
• 🌐 Atoms are mostly empty space; the nucleus is significantly smaller compared to the overall atom size.
• 🔝 The atomic number, found in the periodic table, indicates the number of protons and electrons in an atom.
• 📊 The mass number represents the total count of protons and neutrons in an atom.
• 🔄 Atoms can become ions by losing or gaining electrons, leading to an imbalance in charge.
• 📚 The periodic table organizes elements by their atomic number and provides key information about each element.
• 🔑 The structure, mass, and charge of atomic particles are fundamental to understanding the properties of elements.

Q & A

What are the fundamental building blocks of all matter, including living organisms?

The fundamental building blocks of all matter are tiny particles called atoms.

How many atoms are estimated to be in a single cell?

A single cell is estimated to contain more than 100 trillion atoms.

What are the basic components of an atom's structure?

An atom's basic structure consists of a central nucleus surrounded by electrons that orbit the nucleus in shells.

What particles make up the nucleus of an atom?

The nucleus of an atom is made up of protons and neutrons.

What is the relative mass of protons and neutrons in an atom?

Protons and neutrons have the same mass, with a relative mass of one.

How does the mass of an electron compare to that of a proton or neutron?

Electrons have a mass approximately two thousand times smaller than that of protons or neutrons, often considered very small or even negligible.

What are the charges of protons, neutrons, and electrons?

Protons have a positive charge (+1), neutrons are neutral (no charge), and electrons have a negative charge (-1).

Why is the number of protons in an atom significant?

The number of protons, also known as the atomic number, determines the element that the atom is.

What is the term for an atom that has lost or gained electrons, resulting in an imbalance of charge?

An atom that has lost or gained electrons and has an imbalance of charge is called an ion.

How does the periodic table represent different types of atoms or elements?

The periodic table represents different types of atoms or elements through boxes called nucleus symbols, each with an elemental symbol, atomic number, and mass number.

What does the atomic number indicate about an element's atom?

The atomic number indicates the number of protons in an atom of that element, which in turn tells us the number of electrons in a neutral atom.

How can you find out the number of neutrons in an atom?

You can find out the number of neutrons in an atom by subtracting the atomic number from the mass number.

Outlines

00:00

🌌 Structure and Composition of Atoms

This paragraph introduces the fundamental concept of atoms, which are the building blocks of all matter, similar to how cells form living organisms. It explains that atoms consist of a central nucleus and orbiting electrons, with the nucleus containing protons and neutrons. The paragraph emphasizes the importance of understanding the atomic structure and the relative mass and charge of its components. Protons have a positive charge and a relative mass of one, neutrons are neutral with the same mass as protons, and electrons have a much smaller mass and a negative charge. The paragraph also touches on the concept of atoms being neutral due to the balance of charges between protons and electrons, and how atoms can become ions by losing or gaining electrons, leading to an imbalance in charge.

05:01

🔬 Elements and Nuclear Symbols in the Periodic Table

The second paragraph delves into the concept of elements, represented by boxes on the periodic table, each with its unique nuclear symbol. The nuclear symbol includes the elemental symbol, which is a one or two-letter abbreviation for the element, and provides crucial information about the element. The atomic number, found at the bottom left of the symbol, indicates the number of protons in the atom, which determines the element's identity. The mass number, located at the top left, represents the total count of protons and neutrons. The paragraph illustrates how to calculate the number of neutrons by subtracting the atomic number from the mass number, using oxygen and lithium as examples. It concludes by reiterating the relationship between the atomic number and the number of electrons in a neutral atom, which is equal to the number of protons.

Keywords

💡Atoms

Atoms are the basic units of matter and the defining structure of elements. In the video, they are described as being made up of a central nucleus and electrons that orbit around it. The concept of atoms is central to understanding the composition of all matter, both living and non-living, as highlighted in the script where it is stated that 'everything... is made up of lots of tiny particles which we call atoms'.

💡Electrons

Electrons are negatively charged subatomic particles that orbit the nucleus of an atom. The video script explains that they move around the nucleus in 'shells,' and although only one is shown for simplicity, in reality, all electrons are in constant motion. Electrons play a key role in chemical bonding and determine the chemical properties of elements.

💡Nucleus

The nucleus is the central part of an atom, composed of protons and neutrons. As mentioned in the script, it is 'surrounded by electrons,' which orbit around it. The nucleus is crucial for defining the identity of an element, as the number of protons within it determines the atomic number of the element.

💡Protons

Protons are positively charged particles found in the nucleus of an atom. The video script states that they have a 'one plus charge' and are crucial for the atom's identity, as the number of protons defines the element. For example, 'all oxygen atoms have eight protons,' which is why oxygen is the element with the atomic number 8.

💡Neutrons

Neutrons are neutral particles in the atomic nucleus, having no charge. They have the same mass as protons but do not contribute to the electrical charge of the atom. The script explains that the number of neutrons can vary among atoms of the same element, affecting the atomic mass but not the chemical properties.

💡Charge

Charge refers to the electrical property of subatomic particles. In the video, it is explained that protons have a positive charge, electrons have a negative charge, and neutrons are neutral. The balance of charges within an atom determines if it is neutral or if it becomes an ion with a net charge.

💡Ions

Ions are atoms or molecules that have a net electrical charge due to the loss or gain of electrons. The video script describes how atoms become ions when they 'lose or gain electrons,' resulting in an imbalance of charges. For instance, an atom with extra electrons becomes a negatively charged ion, while one that has lost electrons becomes positively charged.

💡Atomic Number

The atomic number is the number of protons in the nucleus of an atom, which defines the element. The script emphasizes its importance by stating that 'the atomic number... tells us how many protons the atoms of that element have.' For example, oxygen has an atomic number of 8, indicating it has 8 protons.

💡Mass Number

The mass number is the total number of protons and neutrons in an atom's nucleus. The video script explains how to calculate the number of neutrons by subtracting the atomic number from the mass number, as illustrated with oxygen 'having eight neutrons' calculated by 16 (mass number) minus 8 (atomic number).

💡Elements

Elements are pure substances that consist of only one type of atom. The video script introduces the periodic table, which contains boxes representing different elements or types of atoms. Each element is defined by its atomic number, and the script uses oxygen and lithium as examples, with their respective atomic numbers being 8 and 3.

💡Nuclear Symbols

Nuclear symbols, also known as element symbols, are one or two-letter abbreviations that represent elements. The video script discusses how these symbols, such as 'O' for oxygen and 'Li' for lithium, provide information about the element, including its atomic number and mass number.

Highlights

Atoms are the fundamental building blocks of all matter, both living and non-living, and are composed of subatomic particles.

Each atom has a basic structure consisting of a central nucleus surrounded by orbiting electrons in shells.

Protons and neutrons make up the nucleus, with protons carrying a positive charge and neutrons being neutral.

Electrons have a negative charge and are much smaller in mass compared to protons and neutrons.

The atomic number, found in the periodic table, indicates the number of protons and thus defines the element.

The mass number represents the total count of protons and neutrons in an atom.

The number of neutrons can vary within atoms of the same element, leading to different isotopes.

Atoms are mostly empty space, with the nucleus being significantly smaller compared to the overall atom size.

The radius of an atom is approximately 0.1 nanometers, indicating its minuscule size.

Atoms can become ions by losing or gaining electrons, resulting in an imbalance of charges.

Ions can be either positively or negatively charged depending on the electron count relative to protons.

The periodic table organizes elements by their atomic number and provides key information about each element.

Nuclear symbols in the periodic table convey the element's symbol, atomic number, and mass number.

The atomic structure and charge balance are crucial for understanding chemical reactions and properties of elements.

Different elements have unique atomic structures, which determine their distinct chemical and physical properties.

The video aims to provide a foundational understanding of atomic structure and its significance in chemistry.

Transcripts

now just like living organisms are made

up of lots of tiny cells

everything whether it's living

non-living or even a cell itself is made

up of lots of tiny particles which we

call atoms

in fact they're so tiny that a single

cell probably contains more than 100

trillion of them

and in today's video we're going to

explore just what these atoms are and

what they're made of

the first thing to know is that each

atom is made up of multiple smaller

particles

and its basic structure is a central

nucleus surrounded by electrons

which orbit around the nucleus in rings

that we call shells

although we've only shown one electron

orbiting here in reality all of the

electrons would be moving all the time

the nucleus itself is made up of two

different types of particles

protons

and neutrons which are packed together

in a tight ball

now the most important thing to remember

here is the structure of the atom that

we've just been through

and also the relative mass and charge of

each of the particles

the protons and the neutrons have the

same mass

so we say that they both have a relative

mass of one

electrons meanwhile are comparatively

tiny and have a mass two thousand times

smaller

which is often written as just very

small

or sometimes even zero

charge is a bit different though

protons are positive and have a one plus

charge

and you can remember this as both proton

and positive begin with a p

neutrons have no charge so we say

they're neutral

and this is even easier to remember

because the words neutron and neutral

both start exactly the same way

lastly electrons have a negative charge

which is the same size as the positive

charge of the proton so minus one

it can be easy to get all of these mixed

up but the best way to remember it is

that we have positive protons

and neutral neutrons

and then we know that the electrons are

the only one left so they must be the

negative ones

and remember that both of the particles

in the nucleus have a relative mass of

one but the electrons on the outside are

much tinier

the size of an atom depends on which

element it is

and we'll see what elements are in the

next video

but basically they are the different

types of atoms

in general we can say that atoms have a

radius of around 0.1 nanometers

most of an atom is actually empty space

because we measure from the nucleus all

the way to the outer electrons orbit

it's kind of like the solar system you

have one big thing in the middle and

lots of smaller things orbiting it

but between these things is mostly empty

space

now although it looks pretty big in this

picture the nucleus is actually really

tiny

if we compared its width to the width of

the atom itself

the nucleus is 10 000 times smaller

although the electrons are actually even

smaller

and if we were to draw them to scale

they'd be too small to see

in this atom that we've drawn we have

three protons in the nucleus

and three electrons orbiting it

because the number of protons and

electrons is equal

the positive and negative charges

balance out

and so overall the atom is neutral

atoms can lose or gain electrons though

in which case the charges would no

longer balance

and the overall atom would become

charged

when this happens we stop calling it an

atom and instead call it an ion

for example if we gave our atom an extra

electron

we'd still have three protons

but four electrons

and so the charges would no longer

balance

and it would now be a negative ion

because there's more negative electrons

than positive protons

we'd call this a one minus negative ion

because it only has one extra electron

while if our ion had another extra

electron

it would then have two extra electrons

overall and be a two minus negative ion

on the other hand if an atom loses

electrons

then there'll be more positive protons

and negative electrons

so we get a positive ion

and in this case we have three positive

protons but only two negative electrons

so our ion would have a one plus charge

now we take a look at it in detail in

another video but this here is the

periodic table

and each box in the table represents a

different type of atom

which we call an element

so this box here represents the element

oxygen

and this one is the element of lithium

we call these boxes nucleus symbols

and they tell us a whole bunch of

information about the element

to see exactly what they tell us let's

take a look at the nuclear symbols of

oxygen and lithium

the first thing to notice is the

elemental symbol

which is the one or two letter symbol

that represents that element

so o represents oxygen

and li represents lithium

then in the bottom left corner we have

the atomic number

which tells us how many protons the

atoms of that element have

so all oxygen atoms have eight protons

and all lithium atoms have three protons

and this is actually really important

as it's the number of protons in an atom

that determines which element that atom

is

lastly in the top left we have the mass

number

which tells us the total number of

neutrons and protons in that asom

so if we wanted to find out how many

neutrons oxygen has

we would do the mass number

minus the atomic number

which in this case would be 16 minus

eight

so it has eight neutrons

the number of neutrons an atom has isn't

always the same as the number of protons

though

for example lithium has a mass number of

seven

so to find the number of neutrons

lithium has

we would do seven

minus three

which equals four

so lithium has four neutrons

even though it only has three protons

as we said at the beginning of the video

the number of protons and electrons in

an atom is always the same

so the atomic number also tells us how

many electrons the atom has which means

oxygen would have eight electrons and

lithium would have three

anyway that's all for today so hope you

found that video useful and we'll see

you next time