Chemia: Stężenie procentowe roztworu

Stężenie procentowe roztworu (Cp) to liczba gramów substancji rozpuszczonej w 100g roztworu.

Cp = ms × 100% ÷ mr

Cp - Stężenie procentowe roztworu
ms - Masa substancji rozpuszczanej
mr - Masa roztworu

mr = mw + ms
ms - Masa substancji rozpuszczanej
mw - Masa wody (rozpuszczalnika)
mr - Masa roztworu

Chemia: Rodzaje roztworów

Rozpuszczalność substancji - maksymalna liczba gramów substancji, którą można rozpuścić w 100g rozpuszczalnika w danej temperaturze, aby otrzymać roztwór nasycony.

Roztwór nasycony - roztwór, w którym w danej temperaturze nie można już rozpuścić więcej danej substancji.

Rozpuszczalność większości substancji stałych w wodzie zwiększa się wraz ze wzrostem temperatury.
Rozpuszczalność gazów w wodzie zmniejsza się wraz ze wzrostem temperatury.
 


Roztwór nienasycony - roztwór, w którym w danej temperaturze można jeszcze rozpuścić pewną ilość danej substancji.

Roztwór stężony - roztwór, w którym masa substancji rozpuszczanej jest znaczna (kilkadziesiąt procent) w stosunku do masy rozpuszczalnika (wody).

Roztwór rozcieńczony - roztwór, w którym masa substancji rozpuszczanej jest mała (kilka procent) w stosunku do masy rozpuszczalnika (wody).

Roztwór właściwy - roztwór, w którym cząstki substancji rozpuszczanej mają rozmiary mniejsze 10-9m.

Koloid - mieszanina, w której cząstki substancji rozpuszczanej mają rozmiary od 10-9m do 10-7m.

Zawiesina - mieszanina cieczy i substancji rozpuszczanej, której cząstki mają rozmiary większe od 10-7m.

Physics: Energy Conversion and Fossil Fuels

Formation of Fossil Fuels

Source: TesTeach

A fuel is a material that stores chemical potential energy.
Coal, petroleum, and natural gas, are known as fossil fuels.
Fossil fuels contain energy that came from the sun. In fact, the sun is the major source of energy for most of Earth's processes.

When ancient animals and plants died, the chemical potential energy they had stored was trapped within them. This is the chemical potential energy that is found in coal.

Use of Fossil Fuels

Fossil fuels can be burned to release the potential chemical energy stored millions of years ago. The process of burning fuels is known as combustion. During combustion, the fuel's chemical potential energy is converted into thermal energy.

Biology: Angiosperms

An angiosperm is a plant that produces seeds that are enclosed in a fruit.
Ovary is where seeds develop, it is located within an angiosperm's flower - the reproductive structure.
Two characteristics of angiosperms are that they produce flowers and fruits.
Angiosperms live almost everywhere on Earth.

The Structure of Flowers

Source: Pearson Education

All flowers have the same function - reproduction.

When a flower is still a bud, it is enclosed by leaflike structures called sepals. Sepals protect the developing flower. After the sepals fold back, the petals are revealed.

Within the petals are the flower's male and female reproductive parts.

stamens

The stamens are the male reproductive parts. The thin stalk is called the filament. Pollen is produced in the knob, or anther, at the top of the stalk.

pistils

The pistils are the female parts which are usually found in the center of the flower. The sticky tip of the pistil is called stigma. A slender tube, called a style, connects the stigma to a hollow structure at the base of the flower. This hollow structure is the ovary, which contains one or more ovules.

Reproduction

Source: askIItians

First, pollen falls on a stigma. In time, the sperm cell and egg cell join together in the flower's ovule. The zygote develops into the embryo part of the seed.

Types of Angiosperms

Source: Wikipedia

Angiosperms are divided into two major groups: monocots and dicots.

monocots

The flowers of a monocot usually have either three petals or a multiple of three petals. Monocots usually have long, slender leaves with veins that run parallel to one another. The bundles of vascular tissue in manocot stems are usually scattered randomly throughout the stem.

dicots

The flowers of dicots often have either four or five petals or multiples of these numbers. The leaves are usually wide, with veins that branch off from one another. Dicot stems usually have bundles of vascular tissue arranged in a circle.

Biology: Vitamins

Source: perfectbody.fit

Vitamin A

Source: Organic Facts

Benefits:

• Protect eye care
• Provides immune support
• Fights inflammation
• Supports skin health and cell growth

Found in:

• Carrots
• Meat
• Eggs
• Butter
• Mango

Vitamin C

Source: Organic Facts

Benefits:

• Promotes healthy skin
• Improves mineral absorption
• Fights of colds and flu
• Improves immune system 

Found in:

• Guava
• Orange
• Lemon
• Kiwi
• Strawberry

Vitamin D

Source: Organic Facts

Benefits:

• Contributes to bone health
• Helps with concentration and Memory
• Enhances our immune system
• Helps manage blood sugar levels

Found in:

• Sunlight
• Salmon
• Tuna
• Mushrooms
• Milk

Vitamin E

Source: Organic Facts

Benefits:

• Repairs damaged skin
• Balances cholesterol
• Prevents diseases development
• Thickens hair

Found in:

• Sunflower Seeds
• Almonds
• Hazelnuts
• Wheat Germ
• Avocado

Vitamin K

Source: Organic Facts

Benefits:

• Supports heart health
• Improves bone density
• Improves brain function
• Helps maintain teeth and gum
• Helps blood clotting

Found in:

• Kale
• Cabbage
• Cucumbers 
• Broccoli
• Prunes

Vitamin B

Source: Skin Store

B-12

Benefits:

• Helps maintain energy levels
• Needed for healthy skin and hair
• aids in digestion
• Needed for healthy pregnancy
• Prevents memory loss

Found in:

• Eggs
• Cheese
• Milk
• Fish
• Red meat

B-6

Benefits:

• Maintains healthy blood vessels
• Protects eye health
• Supports brain function
• Can improve your mood
• Helps regulate sleep cycle 

Found in:

• Tuna
• Potatoes
• Avocado
• Chickpeas
• Chicken breast 

B-1

Benefits:

• Maintain a healthy metabolism
• Prevents nerve damage
• Boost immunity
• Treats alcoholism
• Enhances learning

Found in:

• Seaweed
• Beans
• Sunflower seeds
• Peas
• Asparagus 

B-2

Benefits:

• Helps support eye health
• Needed for maintaining proper energy levels
• Protects healthy hair and skin
• Prevents Migraines
• Helps maintain energy levels 

Found in:

• Seaweed
• Liver meat
• Almonds
• Eggs
• Organ meat

B-3

Benefits:

• Improves cholesterol levels
• Can help treat diabetes
• Maintains skin health
• Aids in proper brain function
• Helps with joint mobility

Found in:

• Tuna
• Lamb
• Salomon
• Mushrooms
• Turkey

B-9
Folic Acid

Benefits:

• Reduces the chance of birth defects
• Helps in growth of red blood cells

Found in:

• Liver
• Avocado
• Broccoli
• Spinich
• Liver 

Chemistry: Understanding Solutions

Source: socratic.com

Solutions and Suspensions

Suspension is a mixture in which particles can be seen and easily separated by settling or filtration.

Solution - is a well-mixed mixture.

Unlike a suspension, a solution has the same properties throughout. Solutions and suspensions also differ in the size of their particles and the way the parts of the mixtures can be separated. Dissolved particles are much smaller than suspended particles.

Solvents and Solutes

All solutions have at least two parts: the solvent and one or more solutes. The solvent is the part of a solution present in the largest amount. It dissolves the other substances. A substance that is present in a solution in a smaller amount and dissolved by the solvent is a solute.

Solutions without water

You don't need a liquid solvent to make solutions. A solution be made of combinations of gases, liquids, or solids.

Particles in a Solution

Whenever a solution forms, particles of the solute leave each other and become surrounded by particles of the solvent.

Colloids

A colloid is a mixture with small undissolved particles that do not settle out.

Solutions and colloids differ in the size of their particles and how they affect the path of light. Unlike a solution, a colloid contains particles large enough to scatter a light beam.

Lower freezing point

Solutes lower the freezing point of a solvent.

Higher boiling point

Solutes raise the boiling point of a solvent.

Biology: Gymnosperms

What are Gymnosperms

A gymnosperm is a seed plant that produces naked seeds. The seeds of gymnosperms are "naked" because they are not enclosed by any protective covering.
Many gymnosperms have needlelike or scalelike leaves, and deep-growing root systems. Few kinds of gymnosperms are shrubs or vines, most are trees.

Gymnosperms are the oldest type of seed plant.

Gymnosperms are classified into four group: the cycads, the ginkgo, the gnetophytes, and the conifers.
                                             

Source: Wikipedia

Reproduction

Source: Loving Biology

Most gymnosperms have reproductive structures called cones. Cones are covered with scales. Most gymnosperms produce two types of cones: male cones and female cones.

Male cones produce tiny grains of pollen. Pollen contains the microscopic cells that will later become sperm cells.

Female cones contain at least one ovule at the base of each scale. An ovule is a structure that contains an egg cell. After fertilization occurs, the ovule develops into a seed.

First, pollen falls from a male cone onto a female cone. In time, a sperm cell and an egg cell join together in an ovule on the female cone. After fertilization occurs, the zygote develops into the embryo part of the seed.

Pollination

Pollination is the transfer of pollen from male reproductive structure to a female reproductive structure.

Chemia: Woda jako rozpuszczalnik

Dipol - cząsteczka mająca dwa bieguny: dodatni (+) i ujemny (-), na przykład cząsteczka wody.

Source: Molecular Cell Biology

Emulsja - mieszanina niejednorodna dwóch nierozpuszczających się w sobie cieczy, z których jedna jest rozproszona w drugiej w postaci małych kropelek.

Source: epodreczniki

Rozpuszczanie - wnikanie cząsteczek jednej substancji między cząsteczki drugiej substancji.

Cząsteczki wody (dipole) mają zdolność asocjacji, czyli łączenia się pojedynczych cząsteczek w większe grupy, dzięki obecności biegunów (+) i (-) w cząsteczce.
Przykładami dipoli są też m.in. cząsteczki następujących związków chemicznych: chlorowodoru HCl, fluorowodoru HF i amoniaku NH3.

Biology: The Characteristics of Seed Plants

They have vascular tissue and use seeds to reproduce. They have leaves, stems, and roots.
They have complex life cycles include the sporophyte and gametophyte.

Vascular Tissue

Source: SCQ

Most seed plants live on land. The thick walls of the cells in the vascular tissue help support the plants. In addition, water, food, and nutrients are transported throughout the plants in vascular tissue.

Two types of vascular tissue, phloem through which food moves. Water and nutrients travel in the vascular tissue called xylem. The plant's roots absorb water and nutrients from the soil.

Seeds

Seeds are structures that contain a young plant inside a protective covering. Seed plants do not need water in the environment to reproduce. This is because the sperm cells are delivered directly to the regions near the eggs. After sperm cells fertilize the eggs, seeds develop and protect the young plant from drying out.

Source: Wikipedia

A seed has three important parts - and embryo, stored food, and a seed coat.
The young plant that develops from the zygote, or fertilized egg, is called the embryo. The embryo already has the beginnings of roots, stems, and leaves.

Food is stored inside one or two seed leaves, cotyledons.

Outer covering of a seed is called the seed coat.

Seed Dispersal

Source: Study.com

To develop into a new plant, a seed needs light, water, and nutrients.

The scattering of seeds is called seed dispersal.

Germination

Source: The k8 school

Germination is the early growth stage of the embryo. It begins when the seed absorbs water from the environment.

First, the embryo's roots grow downward, then its leaves and stem grow upward.

Leaves

Source: Britannica

Leaves capture the sun's energy and carry out the food-making process of photosynthesis.

The Structure of a Leaf

Source: Wikipedia

The leaf's top and bottom surface layers protect the cells inside. Between the layers of cells inside the leaf are veins that contain xylem and phloem. The underside of the leaf has small openings, or pores, called stomata.

The stomata open and close to control when gases enter and leave the leaf.

The Leaf and Photosynthesis

Source: Wikipedia

The photosynthesis occurs in the chloroplasts of plant cells. The cells that contain the most chloroplasts are located near the leaf's upper surface, where they are exposed to the sun.

Carbon dioxide enters the leaf through open stomata. Water, which is absorbed by the plant's roots, travels up the stem to the leaf through the xylem. During photosynthesis, sugar and oxygen are produced from the carbon dioxide and water.

The sugar enters the phloem and then travels throughout the plant.

Controlling Water loss

Source: Wikipedia

The process by which water evaporates from a plant's leaves is called transpiration.

Stems

Source: Wikipedia

The stem carries substances between the plant's roots and leaves. The stem also provides support for the plant and holds up the leaves so they are exposed to the sun. In addition, some stems, such as those of asparagus, also store food.

The Structure of a Stem

Source: Wikibooks

Herbaceous stems are soft. Woody stems are hard and rigid.

Herbaceous and woody stems consist of phloem and xylem tissue as well as many other supporting cells.

Woody stems have bark, which helps protect the cells inside it, and inner layers of heartwood for additional support. Inside the outer bark layer is the phloem. Inside the phloem is a layer of cells called the cambium. Cambium divide to produce new phloem and xylem.

In the center of the stem is material called the pith. Pith stores food and water.

Annual Rings

Source: Picky Wallpaper

Annual rings are made of xylem. Xylem cells that form in the spring are large and have thin walls because they grow rapidly. They produce a wide, light brown ring. Xylem cells that form in summer grow slowly and, therefore, are small and have thick walls. They produce a thin, dark ring. One pair of light and dark rings represents one year's growth.

Roots

Source: LMC lambark

Roots anchor a plant in the ground and absorb water and nutrients from the soil.

Types of Roots

Source: The Visual Dictionary 

Two types of root systems: taproot and fibrous.

Taproot is a long, thick main root.

Fibrous root systems consist of several main roots that branch repeatedly to form a tangled mass of roots and soil.

United Nations

The United Nations (UN) 

is the world's largest international organization and nearly every country is a member.

United Nations Educational Scientific and Cultural Organization (UNESCO)

UNESCO aims to improve education throughout the world by building schools and training teachers especially in poorer areas. It promotes international cooperation and stresses mutual respect and shared knowledge. 

International Monetary Fund (IMF)

The IMF offers loans to poorer countries and tries to stabilize the world economy. By working with its members from 189 governments, it aims to promote economic growth, better living and standards, international trade, and higher employment.

World Meteorological Organization (WMO)

Everyone can be affected by charges in the Earth's atmosphere, weather, climate, oceans, and water resources. The WMO plays a powerful role in helping to protect humanity from natural disasters by sharing data, technology, training, and research.

International Labour Organization (ILO)

The ILO pushes for better working conditions and equal opportunities, and promotes human rights around the world.

Food and Agricultural Organization (FAO)

The FAO was set up to address the problem of hunger around the globe. It advises countries on growing crops, fishing, forestry, modernizing production, and good nutrition.

International Fund for Agricultural Development (IFAD)

Like many UN agencies, IFAD seeks to eliminate poverty in poorer countries. It works not only to improve food production, but also helps people in rural areas access technology and financial services.

World Intellectual Property Organization (WIPO)

WIPO helps protect work with patents, copyright, and trademarks. It ensures that writers, designers, artists, and inventors benefit from their creative ideas.

International Maritime Organization (IMO)

World experts meet under the IMO to help prevent shipping disasters, improve ship design, and discuss the prevention of pollution by the maritime industry. Its motto is "Safe, Secure, and Efficient Shipping on Clean Oceans."

World Tourism Organization (WTO)

Developing countries are encouraged to improve access for tourists and reap the benefits. The WTO helps to minimize the environmental and social impacts with a Code of Ethics for Tourists.

International Telecommunication Union (ITU)

The ITU deals with information and technology issues. It tries to coordinate satellite use, build better infrastructure in poorer countries, and improve communications across the globe.

Universal Postal Union (UPU)

The non-political organization works within the UN to offer advice and develop technical services for post worldwide. It works closely with other agencies, such as environment groups, to improve global mail distribution.

United Nations Industrial Development Organization (UNIDO)

The promotion of industry in understand countries is handled by UNIDO. It shares knowledge and expertise, provide technical support, and sets up projects to help poorer people earn a living.

World Bank

This UN agency offers financial assistance and investment to developing countries. Its aim is to eliminate poverty and help countries sustain themselves so they will be less dependent on foreign aid.

World Health Organization (WHO)

The WHO aims to improve health, in poorer countries. In the 1960s, its actions made the deadly smallpox disease extinct. It is now concerned with the effects of climate change, HIV/AIDS, and malaria.

International Civil Aviation Organization (ICAO) 

Safety in the air has improved as a result of the ICAO's focus on standards for pilots, the condition of planes, and the orderly growth of the aviation industry. It is also concerned about the pollution that aircraft can cause to the air.

Biology: Ferns

Ferns have vascular tissue and use spores to reproduce.

Vascular plants are better suited to life on land than nonvascular plants. This is because vascular tissue solves the problems of support and transportation.

Ferns, club mosses, and horsetails still need to grow in moist surroundings.

Ferns first appeared on land about 400 million years ago. There are over 12,000 species of ferns alive today.

In many types of ferns, the developing leaves are coiled at first. These young leaves are often called fiddleheads.

On the underside of mature fronds, spores develop in tiny spore cases. When the spores are released, wind and water can carry them great distances.

Ferns, club mosses and horsetails have true leaves, stems, and roots. They also have a similar life cycle.

Chemia: Wewnętrzna budowa materii

Atom

Materia ma budowę ziarnistą i składa się z maleńkich cząstek, będących w ciągłym ruchu. Atom jest to najmniejsza cząstka pierwiastka chemicznego.

Atom składa się z jądra i elektronów.

Jądro atomu pierwiastka zawiera nukleony, czyli protony (p+) i neutrony (n⁰).

Elektrony znajdujące się na ostatniej powłoce to elektrony walencyjne i one decydują o chemicznych właściwościach pierwiastka chemicznego.

Atomy tego samego pierwiastka chemicznego, różniące się liczbą neutronów w jądrze, noszą nazwę izotopów.

Układ Okresowy Pierwiastków

Pierwiastki chemiczne występujące w przyrodzie i otrzymane sztucznie, uporządkowane według zwiększającej się liczby atomowej, tworzą układ okresowy pierwiastków chemicznych.

Znając położenie pierwiastka chemicznego w układzie okresowym i jego liczbę atomową, można podać wiele informacji o nim i o jego związkach chemicznych.

Atomy tego samego pierwiastka gazowego (z wyjątkiem gazów szlachetnych) łączą się, tworząc cząsteczki pierwiastka chemicznego (O2, H2, N2, Cl2).

Atomy różnych pierwiastków chemicznych łączą się,  tworząc cząsteczki związków chemicznych (H2O, CO2, CaO).

Masy atomów i cząsteczek wyraża się w jednostkach masy atomowej (u)

Atomy łączą się za pomocą wiązań chemicznych, które powstają dzięki oddziaływaniom elektronów walencyjnych. Wiązania chemiczne to wiązania kowalencyjne (atomowe) lub jonowe.

Liczba wiązań, za których pomocą łączą się atomy, tworząc cząsteczki, nosi nazwę wartościowości pierwiastka chemicznego.

Wzór Sumaryczny i Strukturalny

Znając wartościowość pierwiastków chemicznych, można poprawnie pisać wzory sumaryczne i strukturalne związków chemicznych.

Równanie Reakcji Chemicznej

Przebieg reakcji chemicznej przedstawia się za pomocą równania reakcji chemicznej. Równanie reakcji chemicznej jest napisane poprawnie, gdy wzory związków chemicznych i symbole pierwiastków po obu stronach równania jest taka sama, tj. gdy równanie jest uzgodnione.

Równania reakcji chemicznych są podstawą obliczeń stechiometrycznych.