Вопрос школьника по предмету Химия
!СРОЧНО! НЕ ЗНАЕШЬ НЕ ОТВЕЧАЙ.Морська вода Середземного моря моря містить 3,9% різноманітних солей( в основному кухонну сіль). Зробіть неодхідне обчислення й укажіть, яку масу солей можна отримати під час випарювання 200 кг морської води. А 5,7 кг. Б 3,9 кг. В 3,6 кг. Г 7,8кг.
Ответ учителя по предмету Химия
Ответ:
Г
Объяснение:
200*0,039 = 7,8 кг
по формуле растворов
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липень, серпень, вересень, грудень. Коротко. Не більше 8 слів.
The Black Death arrived in Europe by sea in October 1347 when 12 trading ships came to an Italian port after a long voyage across the Black Sea. A crowd of people gathered on the docks to greet the ships. Soon the smiles changed into a horrifying surprise. Most of the sailors aboard the ships were dead, and those who were still alive were fatally ill. They had a high temperature, couldn’t eat and suffered from pain. The sailors were covered in black swellings which gave their illness its name: the Black Death. The Italian authorities made the ‘death ships’ and their sailors leave the port, but it was too late. Over the next five years, the mysterious Black Death (or the plague) would kill almost one-third of the European population.
The Black Death first appeared in Britain in 1348. Since that time the British islands were never totally free of plague.
In the year 1665 the Black Death came to the city of London, even though King Charles II had tried to prevent the epidemic of plague and had forbidden any trade with Holland, where there was a great plague epidemic. Despite the safety measures, in the early spring of 1665 thousands of people died in the poor parts of London. At first the government didn’t pay much attention to this fact. But as the spring turned into a hot summer, the number of deaths rose and panic set in.
The rich aristocracy and royal family left the capital for their houses in the country. They were followed by the merchants, and the lawyers. By June the roads were full with people who wanted to escape London. The Lord Mayor ordered to close the city gates to anyone who did not have a certificate of health. By mid July over 1,000 deaths per week were reported in the city. It was said that dogs and cats spread the disease. By the Lord Mayor’s order, more than 40,000 dogs and 200,000 cats were killed in London. The real effect of this was that the population of the rats, who were the plague carriers, increased. The Black Death began to spread more rapidly.
Anyone who was in constant contact with plague victims, such as doctors, nurses and inspectors, had to carry coloured sticks outdoors so that they could be easily seen and avoided. When one person in a house caught the plague, the house was closed until 40 days after the victim had either recovered or died (usually the latter). The members of the family were not allowed to leave the house either. Special guards were put at the door to see that no one got out.
Throughout the summer the death rate grew till it reached 6,000 people per week in August. From there the disease very slowly went down until the winter. However, King Charles II decided that it was safe to return to the capital only in February of 1666. How many died? It is hard to say. It was said that 100,000 people had died in and around London, though the figure may have been much higher. The Black Death was the worst and the last of the epidemics in Great Britain.
*a plague — чума
The Italian authorities allowed the sick sailors to stay in the town.
1)
True
2)
False
3)
Not stated
Each of the ‘death ships’ had a doctor on board.
1)
True
2)
False
3)
Not stated
King Charles II made attempts to stop the plague.
1)
True
2)
False
3)
Not stated
To get health certificates, people had to pay a lot of money.
1)
True
2)
False
3)
Not stated
The plague epidemic began to slow down when the city got rid of the cats and dogs.
1)
True
2)
False
3)
Not stated
The members of the family with a sick person had to leave London as soon as possible.
1)
True
2)
False
3)
Not stated
August was the peak of the plague epidemic.
1)
True
2)
False
3)
Not stated
There is no documentary evidence about the exact number of people who were killed by the plague.
1)
True
2)
False
3)
Not stated