that a mineral called pitchbende emitted much mor poverful rays than any
she had already found.
9. Now, an element is a chemical substance which so far as is known
cannot be split up into other substances. As Mme. Curie had examined
every known chemical element and none of them had emitted such
powerful rays as pitchblende she could only decide that this mineral must
contain some new element.
Scientists had declared that every element was already known to them.
Bull all Mme. Curie's experiments pointed that it was not so.
Pitchblende must contain some new адц unkllOwn element. There
was no other explanation Уог the powerful rays which it emitted. At that
moment Pierre Curie stopped his own investigations on the physics of
crystals and joined his wife in her effort to find tliose more active
unknown chemical elements.
Scientists call the property of giving out such rays "radioactivity”, alld
Mme. Curie decided to call the new element "radium", because it was more
strongly radioactive thah any known metal.
It is known now that Мте. Curie has given the real basis far the
industrial methods of separating radium and other elements from the
pitchblende and from other minerals. ІПІ903 Marie and Pierre together
with Henry Becquerel were awarded the Nobel Prize in Physics. In 1911
Marie received the Nobel Prize in Chemistrv. But the second prize went to
her alone for in 1906 Pierre ha (1 died tragically in a traffjc
a c cid en i-.М те.
Sklodowska-Curie, the leadillg woman-scielltist, the greatest woman of
her generation, has become the first person to receive a Nobel Prize twice.
UNIT IS
EDUCATION
1.
As long as we .live we continue to learn, and the education we
receive wheh we are young helps us to continue learning. We are taught to
read and write, and are taught many of the essential facts about the world
and shown how to sort them out so that later in life, we shall be able to find
out things ourselves and not to ask other people.
The first teachers were fathers and mothers, but very early in the
istory о man children began to be taught by people other than their
!ath^
and mothers- 11 is thought that schools first started in Egypt 5,000-
o
,
years ago, and that it was the invention of writing which made
them necessary. Reading and writing were quite different from the skills
Достарыңызбен бөлісу: