True or false questions

True. At normal sea-level air pressure, pure water boils at about 100 degrees Celsius, or 212 degrees Fahrenheit. Higher up, the air pressure drops and water boils at a lower temperature.

False. The Moon makes no light of its own. What we call moonlight is sunlight bouncing off the Moon’s surface, with a little light reflected from Earth too.

True. Each color of light bends by a slightly different amount as it passes through glass, so a prism fans white light out into a rainbow-like spectrum.

False. Electrons carry a negative charge. The positive charge in an atom comes from the protons in its nucleus.

True. Dissolved salt gets in the way of ice forming. Fresh water freezes at 0 degrees Celsius, while typical seawater has to cool to about minus 1.8 degrees Celsius.

True. The Moon is about 3,474 kilometers across, while Pluto is about 2,377 kilometers. Pluto is only around two-thirds as wide as our Moon.

True. An atom’s center, the nucleus, is where its protons and neutrons sit. The electrons are outside it, in a cloud around the nucleus.

False. Helium is much lighter than air, which is why helium balloons float up and why it has been used to lift blimps and weather balloons.

False. Rubber is an insulator, so electric current does not flow through it easily. That is why it is used to coat wires and to make electricians' safety gloves.

False. Magnets stick to iron, steel, nickel and cobalt. Aluminum is only very weakly affected by magnets, far too little for a fridge magnet to hold on.

False. Despite the word year, a light-year measures distance. It is how far light travels in one year, roughly 9.5 trillion kilometers or 5.9 trillion miles.

True. Lightning heats the air around it so fast that the air expands with a bang. That sound is thunder, which is why you never get thunder without lightning.

False. Absolute zero, the coldest temperature possible, is minus 273.15 degrees Celsius, or minus 459.67 degrees Fahrenheit. That is zero on the Kelvin scale.

True. Sound is a vibration that needs something to travel through, such as air or water. Empty space has almost nothing to carry it, so astronauts talk by radio.

True. Earth’s inner core is a solid ball made mainly of an iron and nickel alloy. It stays solid, despite extreme heat, because of the enormous pressure at Earth’s center.

True. In a main rainbow, red sits on the outer edge of the arc and violet on the inner edge. In a fainter second rainbow, the order is reversed.

False. Ice is about 9 percent less dense than liquid water, which is why ice cubes float and lakes freeze from the top down.

True. Portugal’s only land neighbor is Spain, which wraps around it to the north and east. The rest of Portugal faces the Atlantic Ocean.

True. Sri Lanka is an island country in the Indian Ocean, just off the southern tip of India across the Palk Strait and the Gulf of Mannar.

True. Venice sits on about 118 small islands in a lagoon, separated by canals and linked by hundreds of bridges.

False. Iceland has around 30 active volcanic systems and erupts often. The Reykjanes Peninsula near Reykjavik has had a run of eruptions since 2021.

True. The Amazon starts in the Andes of Peru and flows east across Brazil before emptying into the Atlantic Ocean.

True. With its huge Arctic islands, Canada has more than 200,000 kilometers of coastline, far more than any other country. Norway, Indonesia and Russia trail well behind.

True. The Dead Sea’s shores are the lowest dry land on Earth, more than 400 meters below sea level, and they keep dropping as the lake shrinks.

False. Lake Titicaca, high in the Andes, lies on the border of Peru and Bolivia. It is the largest freshwater lake in South America.

False. The Pacific is the largest and deepest ocean on Earth. The smallest is the Arctic Ocean.

True. A 2023 recount by Japan’s mapping agency, using digital maps, found 14,125 islands. That is more than double the old official figure of 6,852.

True. The Danube runs from Germany to the Black Sea, passing through or along the borders of ten countries, from Austria and Hungary to Romania and Ukraine.

False. Canada lies far to the north, wholly in the Northern Hemisphere. The equator crosses countries such as Ecuador, Colombia, Brazil, Kenya and Indonesia.

False. Madagascar is in the Indian Ocean, off the southeast coast of Africa, across the Mozambique Channel from the mainland.

True. Antarctica gets so little rain or snow each year that most of it counts as a desert, which makes it the driest continent as well as the coldest.

False. The Andes run down the western side of South America, close to the Pacific coast, from Venezuela and Colombia all the way south to Chile and Argentina.

True. Mongolia is landlocked, sitting between Russia to the north and China to the south, with no border on any sea or ocean.

False. All of Australia lies south of the equator, so it is in the Southern Hemisphere. Even its northern tip, Cape York, is about 10 degrees south.

True. The Vikings were seafaring people from Scandinavia, the area that is now Denmark, Norway and Sweden, who raided, traded and settled across Europe and beyond.

True. Gutenberg, a German craftsman, developed his movable-type printing press in the mid-1400s and printed his famous Bible in the 1450s, changing how books were made in Europe.

False. The Great Fire of London broke out in 1666, not 1966. It started in a bakery on Pudding Lane and burned for about four days.

False. The Industrial Revolution began in Great Britain in the mid-1700s and later spread to Europe and the United States. Japan industrialized much later, in the late 1800s.

True. In 1610 Galileo turned an early telescope on Jupiter and found its four largest moons, now called the Galilean moons: Io, Europa, Ganymede and Callisto.

True. Columbus sailed from Spain in August 1492 and landed in the Bahamas on October 12, 1492. Norse explorers had reached North America about 500 years earlier.

False. Napoleon was born in Ajaccio on the island of Corsica in 1769, a year after Corsica passed from Genoa to France.

True. The Silk Road was not one road but many overland and sea routes that carried silk, spices and ideas between China and Europe for centuries.

False. Queen Victoria reigned for more than 63 years, from 1837 to 1901, one of the longest reigns in British history.

True. Tenochtitlan was built on an island in Lake Texcoco. After the Spanish conquest in 1521, Mexico City was built over its ruins, which lie under today’s historic center.

False. King John sealed Magna Carta at Runnymede, near Windsor, in June 1215, exactly 600 years before the date in the statement.

True. China used paper money long before Europe. Merchants' paper notes appeared in the Tang dynasty, and true paper currency called jiaozi circulated under the Song dynasty by the 11th century.

False. The Colosseum is in the center of Rome, Italy, just east of the Roman Forum. It was built by Roman emperors nearly 2,000 years ago.

False. Julius Caesar ruled Rome as dictator but never became emperor. His adopted heir Octavian, later called Augustus, became the first Roman emperor in 27 BC.

False. George Washington was the first US president, taking office in 1789. Abraham Lincoln was the 16th president and led the country through the Civil War.

True. Bell received a US patent for the telephone on March 7, 1876, a few days before his first successful call to his assistant, Thomas Watson.

True. The Rosetta Stone carries the same decree in hieroglyphs, Demotic and Greek. Comparing them helped Jean-François Champollion crack hieroglyphs in 1822.

True. Fish that swim together in a tight, coordinated group form a school. A looser social group of fish is often called a shoal.

False. Ostriches cannot fly at all. They are flightless birds, but their long, strong legs make them very fast runners.

False. Crocodiles are reptiles. They have scaly skin, lay eggs and do not feed their young on milk the way mammals do.

False. Dolphins are mammals, not fish. They breathe air through a blowhole, give birth to live young and feed their calves milk.

False. Snakes have no movable eyelids, so they cannot blink. Each eye is covered by a clear scale called a spectacle, which is shed with the skin.

True. Penguins are birds, even though they cannot fly. They have feathers and lay eggs, and their wings work as flippers for swimming.

False. Frogs are amphibians, like toads and salamanders. Most start life in water as tadpoles and have moist skin, unlike the dry, scaly skin of reptiles.

True. The platypus is one of the few mammals that lay eggs. Females lay small eggs, then feed the young on milk after they hatch.

True. Many sea stars can regrow an arm they lose to a predator or injury. It can take months, and a few species can grow a whole new body from one arm.

False. Spiders make silk in glands inside the abdomen and draw it out through spinnerets near the rear of the body, not from their mouths.

True. Galápagos giant tortoises are thought to live more than 100 years in the wild, and one at the San Diego Zoo reached an estimated 150.

False. Rabbits are lagomorphs, a separate order from rodents. One clear difference is teeth: rodents have two upper incisors, while rabbits have four, with a small extra pair behind the front ones.

False. Dalmatian puppies are born with plain white coats. Their dark spots start to show in the first few weeks and keep developing for months.

True. Tree sloths spend most of their lives hanging in the rainforest canopy. They come down only now and then, for example to cross to another tree.

False. Whales are mammals, so they breathe air with lungs. They come to the surface and breathe through blowholes, which are nostrils on top of the head.

True. A snail’s mouth holds a radula, a tongue-like ribbon covered in rows of tiny teeth. The snail uses it to scrape or cut food before swallowing.

False. Most owls are nocturnal and hunt at night, helped by large eyes, sharp hearing and silent flight. A few, such as the burrowing owl and northern hawk owl, are active by day.

True. Peanut flowers bloom above ground, then a stalk called a peg grows down into the soil, where the pods and nuts develop.

True. Popcorn is a special variety of corn whose kernels have a tough hull. When heated, moisture inside turns to steam and the kernel bursts open.

False. Pasta is made mainly from wheat, usually durum wheat semolina mixed with water and sometimes eggs. Rice noodles exist, but they are not standard pasta.

True. A raisin is simply a grape that has been dried, either in the sun or by machine. Golden raisins come from the same grapes but are dried mechanically.

False. Feta is a white brined cheese from Greece, made from sheep’s milk or a sheep and goat mix. Since 2002 the EU has protected the name for Greek-made cheese.

True. Paella comes from the Valencia region on Spain’s east coast, where farm workers cooked rice with local ingredients in a wide, shallow pan.

True. Couscous is made of tiny steamed granules of rolled semolina, the coarse flour from hard durum wheat. Some regions also make versions from barley or millet.

True. Wasabi belongs to Brassicaceae, often called the cabbage or mustard family. Its relatives include cabbage, horseradish and mustard.

False. Basmati is a long-grain, fragrant rice from the Indian subcontinent, grown there for centuries. It is not a pasta.

False. Gazpacho is a cold soup of raw, blended vegetables such as tomato, cucumber and pepper. It is a summer favorite in southern Spain.

False. Naan is a leavened flatbread, usually made with wheat flour and often baked in a tandoor, a very hot clay oven. It is not a rice dish.

False. Hummus is made mainly from cooked, mashed chickpeas blended with tahini, lemon juice and garlic. The name itself comes from the Arabic word for chickpeas.

False. Cashews grow on evergreen trees. Each nut hangs from the end of a fleshy, fruit-like stalk called the cashew apple.

True. Cheddar cheese takes its name from Cheddar, a village in Somerset in southwest England, where cheese has been made since at least the 1100s.

False. A pineapple grows from the center of a low, spiky plant rooted at ground level, usually 3 to 6 feet tall. Each plant produces one fruit at a time.

True. Maple syrup starts as watery sap tapped from maple trees, mostly sugar maples. The sap is boiled down until most of the water is gone and it thickens into syrup.

True. The 1935 Parker Brothers game named its properties after places in and around Atlantic City, New Jersey, such as Boardwalk and Park Place. The UK board uses London places instead.

True. Hungarian architecture professor Ernő Rubik invented the cube in Budapest in 1974. It was sold in Hungary as the Magic Cube before its worldwide launch in 1980.

True. In Arthur Conan Doyle’s stories, Holmes and Dr. Watson share rooms at 221B Baker Street in London, rented from their landlady, Mrs. Hudson.

True. Spanish writer Miguel de Cervantes wrote Don Quixote, published in two parts in 1605 and 1615. It is often called one of the first modern novels.

False. Leonardo da Vinci’s Mona Lisa hangs in the Louvre in Paris, where it has been on show for most of the time since 1797.

False. Basketball was invented in 1891 in Springfield, Massachusetts, in the United States. Its inventor, James Naismith, was Canadian, which is why many people guess Canada.

False. The men’s World Cup is held every four years. It began in 1930, and only 1942 and 1946 were skipped because of World War II.

True. English-language haiku are usually set out in three short lines, often 5, 7 and 5 syllables. In Japan, haiku were traditionally printed as a single line.

False. A standard deck has 52 cards, made up of four suits with 13 cards each. Jokers come as extras on top of those 52.

False. A standard ukulele has four strings. Some special versions pair up strings to make six or eight, but the usual instrument has four.

False. Emoji began in Japan, where phone and electronics companies made the first sets. Even the word is Japanese, built from the words for picture and character.

True. Both songs use the same French folk melody from the 1700s, which Mozart later wrote a set of variations on. Baa, Baa, Black Sheep is sung to it too.

True. The Academy’s formal name for the statuette is the Academy Award of Merit. Oscar is the nickname, and it became so common that few people know the official one.

True. A standard English Scrabble set has 100 tiles: 98 with letters on them and two blanks that can stand for any letter.

False. Batman guards Gotham City. Metropolis is the home city of Superman, another DC Comics hero.

True. Shakespeare’s play is set at the royal court of Denmark, and its full title is The Tragedy of Hamlet, Prince of Denmark.