2Na+2H2O=2NaOH+H22*232*402xy0.2gx=4.6gy=8gm(Na2O)=10.8-4.6=6.2gNa2O+H2O=2NaOH622*406.2gzz=8g质量分数w(NaOH)=16/(10.8+100-0.2)*100%=14.46%C=1000pw/M=1000*1.16*14.46%/40=4.2mol/L
写出钠与水反应方程式用生成氢气的质量计算出钠的质量计算浓度有个公式C=1000*密度/M(记不清了,应该是)
2Na+2H2O=2NaOH+H2↑4636802xay0.246:2=x:0.2x=4.6g80:2=y:0.2y=8g36:2=a:0.2a=3.6g10.8克固体中,金属钠是4.6g,NaO为10.8-4.6=6.2gNa2O+H2O=2NaOH6218806.2bz62:80=6.2:zz=8g62:6.2=18:bb=1.8g反应后总的NaOH为:8+8=16g物质的量为:16g/40g/mol=0.4mol反应后水的质量为:100-3.6-1.8=94.6g水的体积为:94.6g/1g/cm^3=94.6mlNaoH的物质量浓度为:0.4mol/(94.6x10^-3)L=4.23mol/L