Дано:
m(р-ра)=180 г. W(c) = m(c) / m(р-ра) *100%
W(c) = 25% m(c)=W(c) * m(р-ра) / 100% = 25 * 180 / 100 = 45 г
Найти:
m(c)
только в варианте "в". в остальных рядах есть вещ-ва с двойными связями
2KClO4+CuCl2=2KCl+Cu(ClO4)2
KCl+H2O=KOH+HCl
2HCl+2F=2Hf+Cl2
Cl2+KIH=KClO+HCl
2KClO+H2SO4=K2SO4+2HCLO
HClO+Ca=HCl+CaO
2HCl+AuCl=AuCl3+H2
Al2(SO4)3+6NaOH=2Al(OH)3+3Na2SO4
2Al(+)+3SO4(2-)+6Na(+)+6OH(-)=2Al(Oh)3+6Na(+)+3SO4(2-)
2Al(3+)+6OH(-)=2Al(OH)3
<span>a) 4NH3+7O2=4NO2+6H2O</span>
<span>N+3 -1e- => N+4 1</span>
<span>O2 +2*2e- => 2O2- 4</span>
<span><span>b)2Al+3i2=2Ali3</span></span>
<span><span>Al -3e- => Al3+ 2</span></span>
i2 +2*1e- => 2i- 3
<span> c)5HNO3+3P+2H2O=3H3PO4+5NO </span>
N+5 +3e- => N+2 5
P -5e- => P+5 3
<span>d)<span>2</span><em>K</em><em>Mn</em><em>O</em>4<span> + </span><span>16</span><em>H</em><em>Cl</em><span> = </span><span>5</span><em>Cl</em>2<span> + </span><span>2</span><em>K</em><em>Cl</em><span> + </span><span>2</span><em>Mn</em><em>Cl</em>2<span> + </span><span>8</span><em>H</em>2<em>O</em></span>
<em>Mn+7 +5e- =>Mn+2 2</em>
<em>2Cl- -1*2e- =>Cl2 5</em>