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1. I (to write) an English exercise now. 2. I (to write) an English exercise at this time yesterday.3. My little sister (to sleep) at this time tomorrow.4. My friends (not to do) their homework now. They (to play) volleyball.5. My friends (not to do) their homework at seven o'clock yesterday. They (to play)volleyball.6. She (to read) the whole evening yesterday.7. Look! My cat (to play) with a ball.8. When I went out into the garden, the sun (to shine) and birds (to sing) in thetrees.9. When you come to my place tomorrow, I (to read) your book.10.I (to watch) TV the whole evening next Sunday..​

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nmakarchuk
Вариант 1. 1)-в ; 2)-г ; 3) H2N-CH2-COOH+NaOH=H2N-CH2-COONa+H2O ; m(NaOH)=200г×12%÷100%=24 г ; m(аминок-оты)=[75г/моль(молярка кислоты)×24г]÷40г/моль(молярка щелочи)=45г. Вариант 2. 1)-б ; 2)-в ; 3) 2H2N-CH2-COOH=H2N-CH2-CO-NH-CH2-COOH+H2O ; m(к-оты)=150г×15%÷100%=22,5г ; m(глицил-глицина)=[22,5г×132г/моль(молярка дипептида)]÷75г/моль(молярка аминокислоты)÷2=19,8г. Вариант 3. 1)-г ; 2)-б ; 3). H2N-CH2-COOH+NaOH=H2N-CH2-COONa+H2O ; m(NaOH)=240г×2%÷100%=4,8г ; m(аминокислоты)=[75г/моль(молярка кислоты)×4,8г]÷40г/моль(молярка щелочи)=9г. Вариант 4. 1)-в ( но вообще ближе к бледно-фиолетовому) ; 2)-в ; 3). H2N-CH2-CO-NH-CH2-COOH+H2O=2H2N-CH2-COOH ; mаминокислоты)=[52,8г×75г/моль×2(молярка аминокислоты их 2 моль)]÷132г/моль(молярка глицил-глицина)=60г.

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1. I (to write) an English exercise now. 2. I (to write) an English exercise at this time yesterday.3. My little sister (to sleep) at this time tomorrow.4. My friends (not to do) their homework now. They (to play) volleyball.5. My friends (not to do) their homework at seven o'clock yesterday. They (to play)volleyball.6. She (to read) the whole evening yesterday.7. Look! My cat (to play) with a ball.8. When I went out into the garden, the sun (to shine) and birds (to sing) in thetrees.9. When you come to my place tomorrow, I (to read) your book.10.I (to watch) TV the whole evening next Sunday..​
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