BASES

Many cleaning products, such as soap and oven cleaner, are bases. Bases neutralize (cancel out) acids. Alkalis are bases that dissolve in water. Strong bases, such bleach, are corrosive and burn skin. Bases contain particles called hydroxide ions. The more hydroxide ions a base contains, the stronger it is.

NEUTRAL WASP STING

People used to think that a wasp sting contained a base. In fact, it contains a complex protein, which is neutral. This means that the sting is neither a base nor an acid. The wasp punctures the skin with its hollow stinger. It then pumps the protein through the stinger and into the wound. The protein contains poisons, which cause pain and swelling.

LIMESTONE

Limestone is an important base that is dug from the earth in quarries. It comes from calcium carbonate, which formed millions of years ago from the compressed remains of sea-shells and other marine life. Once quarried, limestone is crushed and used to make cement, fertilizers, paints, and ceramics.

Copyright © 2007 Dorling Kindersley

highlights

Special Books for the Kids You Love
Celebrate 20 years of sharing love to the moon and back with the anniversary edition of Guess How Much I Love You, one of the world’s best-loved picture books. Plus, search our Book Finder for more great book picks. Brought to you by Candlewick Press.

Vote Now for the Children's & Teen Choice Book Awards
Voting is open now through May 3 for the Children's and Teen Choice Book Awards — the only national book awards program where the winning author, illustrator, and books of the year are selected by young readers. Encourage your child to vote for his favorites today!

Top 10 Math & Science Apps for Your Whiz Kid
Looking for the best math and science apps for kids? Check out these cool apps for all ages, which will grow your child's love of the STEM subjects (science, technology, engineering, and math).

Registered for Kindergarten — Now What?
Wondering what to do now that you've signed your child up for kindergarten? Try our award-winning Kindergarten Readiness app! This easy-to-use checklist comes with games and activities to help your child build essential skills for kindergarten. Download the Kindergarten Readiness app today!

stay connected

Sign up for our free email newsletters and receive the latest advice and information on all things parenting.

Enter your email address to sign up or manage your account.

Facebook icon Facebook icon Follow Us on Pinterest

editor’s picks