На лакмус красный - кислоты H2SO4, HCl
<span>синий щелочи - Ca(OH)2, KOH ))</span>
1) <span>ВаО+<span>Н2O=<span>Ba(OH)2</span></span></span>
<span><span><span>2) Mg+H2SO4=<span>MgSO4+H2|</span></span></span></span>
<span><span><span><span>3) <span>FeCl</span>3+3<span>LiOH=3<span>LiCl3+Fe(OH)3</span></span></span></span></span></span>
<span><span><span><span><span><span>4)<span>CuO+ H2|=H2O+Cu</span></span></span></span></span></span></span>
Б) <span> уменьшить концентрацию TiCl4 в 3 раза</span>