Радиус атомов уменьшается. По периодам радиус увеличивается, а по группам уменьшается.
<span>Ca+<span>2<span>H2IO</span></span> → <span>Ca<span>(OH)</span>2</span>+<span>H2
</span></span><span><span>Ca<span>(OH)</span>2</span>+<span>H2CO3</span> → <span>CaCO3</span> +<span>2<span>H2O
</span></span></span><span><span>CaCO3</span> → <span>CaO</span>+<span>CO2
</span></span><span><span>CaO</span>+<span>2<span>HCl</span></span> → <span>CaCl2</span>+<span>H2O
</span></span><span><span>Na2CO3</span> +<span>CaCl2</span> → <span>2<span>NaCl</span></span>+<span>CaCO<span>3
</span></span></span>
1 Н(NO3)2. 2 <span>Ca(OH)<span>2 . 3 NO 4.</span></span><span>MgO </span>
Fe + CuSO4 = Cu + FeSO4
FeSO4 + 2KOH = Fe(OH)2 + K2SO4
Fe(2+) + SO4(2-) + 2K(+) +OH(-) = Fe(OH)2 + 2K(+) + SO4(2-)
Fe(2+) + +OH(-) = Fe(OH)2
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