初三模考试题精心整理汇编 County continuation records has examined and approved the draft, spirit, believe, comprehensive Yearbook ooved the draft, spirit, believe, comprehensive Yearbook of zhuanglang already prepared draft, entered the phase of evaluation. Civil air defense work2 County continuation records has examined and approved the draft, spirit, believe, comprehensive Yearbook of zhuanglang already prepared draft, entered the phase of evaluation. Civil air defense work京睿试题库 :....: 为了孩子的将来保驾护 County continuation records has examined and approved the draft, spirit, believe, comprehensive Yearbook of zhuanglang already prepared draft, entered the phase of evaluation. Civil air defense work 14.将pH=10的氢氧化钠溶液加水稀释后,所得溶液的pH可能是 A.6 B.8 C.11 D.14 15.配制一定溶质质量分数的***化钠溶液,下列操作不正确的是 A B C D 16.丙氨酸(C3H7O2N)是一种氨基酸,下列有关丙氨酸的说法正确的是 A.含有2个氧原子 B.相对分子质量是89 g C.碳元素的质量分数最大 D.碳、氢元素的质量比为3︰7 17.下列做法不正确的是 A.家用电器着火,立即用水浇灭 B.天然气泄漏,立即关闭阀门并开窗通风 C.不慎将燃着的酒精灯碰倒,立即用湿布盖灭 D.稀释浓硫酸时,将浓硫酸缓慢注入水中并搅拌 18.下列物质露置在空气中一段时间后,质量会减少的是 A.浓盐酸 B.烧碱 C.浓硫酸 D.生石灰 19.下列对应的化学方程式书写正确的是 A.工业上用赤铁矿(主要成分是Fe2O3)炼铁:3CO + Fe2O3=3CO2 + 2Fe B.用含有还原性铁粉的麦片补铁:2Fe + 6HCl=2FeCl3 + 3H2↑ C.用氢氧化钠处理含硫酸的废水:NaOH + H2SO4=Na2SO4 + H2O D.正常的雨水显酸性:CO2 + H2O=H2CO3 液面 不下降 弹簧夹 液柱上升, 一段时间 后不下降 20.下列实验现象不能说明装置气密性良好的是 [来源:] A