Вопрос школьника по предмету Химия
задача. вычислите сколько по массе соли и воды нобхожимо для приготовления 125грамм 20-процентного раствора соли помогите пожалуйста срочно надо
Ответ учителя по предмету Химия
По формуле нахождения массовой доли находим массу соли (вещества)
125г*0.2=25г
масса воды 125г-25г=100г
Похожие вопросы от пользователей
Canada is the second largest country in the world. It covers the northern part ofNorth America and its total area is 9,975,000 square kilometres. Canada’s onlyneighbour is the USA. The border between the two countries is the longest unguardedborder in the world.Canada’s motto, «From Sea to Sea,» is particularly appropriate because thecountry is bounded by three oceans — the Pacific, the Arctic and the Atlantic. Its vastarea includes some of the world’s largest lakes and countless smaller ones. One-thirdof all fresh water on Earth is in Canada.Canada’s name comes from an Indian word kanata, which means «village». Thefirst French settlers used the Indian name for the colony, but the official name was»New France». When the area came under the British rule in 1897, the new countrywas called the Dominion of Canada, or simply Canada. Canada is a union of tenprovinces and two territories.Compared with other large countries, Canada has a small population, only about27,300,000. The country, however, is one of the world’s most prosperous. Canadiansdeveloped its rich natural resources and, in the process, have achieved a high standardof living.Canada is a constitutional monarchy. It is a member of the Commonwealth ofNations and Queen Elizabeth II is its official head of state. Although the Queen holdsthis high position, she doesn’t rule. She serves as a symbol of British tradition. Herrepresentative in Canada is the Governor General, whom she appoints on the adviceof the Canadian Prime Minister. The Governor’s duties are limited to symbolic,mostly ceremonial acts.The real power belongs to the Prime Minister and his Cabinet. The CanadianParliament consists of two chambers: the House of Commons and the Senate.There are two official languages in the country: English and French. All Canadianchildren have to learn both French and English at school, but Francophones andAnglophones do not enjoy learning each other’s language.»We have two races, two languages, two systems of religious belief, two sets oflaws … two systems of everything,» said one Canadian journalist.There was a time when Quebec Province (its population is 90% French) decided toseparate from Canada and form a new country. Fortunately, the movement has waned.The capital of Canada is Ottawa