25℃、101 kPa下,碳、氢气、甲烷和葡萄糖的燃烧热依次是393.5 kJ/mol、285.8 kJ/mol
890.3 kJ/mol、2800 kJ/mol,则下列热化学方程式正确的是
| A.C(s)+O2(g)=CO(g) △H=" ―393.5" kJ/mol |
| B.2H2O(l)=2H2(g)+O2(g) △H=" +571.6" kJ/mol |
| C.CH4(g)+2O2(g)=CO2(g)+2H2O(g) △H=" ―890.3" kJ/mol |
| D.C6H12O6(s) +6O2(g)=6CO2(g)+6H2O(l) △H=" ―2800" kJ/mol |
在298k时有下面两个反应:
①C(s)+
O2(g) =" CO" (g)
H1= —110.5kJ/mol
②C(s)+ O2(g) = CO2 (g)
H2= —393.5kJ/mol
则C(s)+ CO2(g) =" 2CO" (g) 的
H为
| A.+ 283.5kJ/mol | B.+ 172.5kJ/mol |
| C.—172.5kJ/mol | D.—504kJ/mol |
下列说法正确的是
| A.电极方程式:Cu-2e- = Cu2+,既能发生在原电池中,又能发生在电解池中 |
| B.某温度下,10mL 0.1mol/L的H2SO4溶液与10mL 0.4 mol/L的KOH溶液混合后,pH=13 |
| C.断裂1mol H-H、N-H、N≡N键需吸收的能量分别为a kJ、b kJ、c kJ, 则2NH3( g) |
| D.中和等体积的醋酸溶液,消耗等pH值的氨水和氢氧化钠溶液的体积分别为V1、V2,则V1<V2 |
已知:①2CO(g)+ O2(g)="=" 2CO2(g) ΔH1=" " -566.0kJ/mol
②C(s)+O2(g)==CO2(g) ΔH2=" " -393.5kJ/mol
则1molC(s)在氧气中燃烧生成CO时的ΔH值为:
| A.+172.5 kJ/mol | B.-172.5 kJ/mol | C.+110.5kJ/mol | D.-110.5kJ/mol |
已知H2(g)+Br2(l)="2HBr(g) " △H=-72kJ/mol,蒸发1mol 液溴变Br2(g)需要吸收的能量为30kJ,其它相关数据如下表:
| | H2(g) | Br2(g) | HBr(g) |
| 1mol分子中的化学键断裂时需要吸收的能量/kJ | 436 | a | 369 |
A.404 B.260
已知(1)H2(g)+1/2O2(g)===H2O(g) △H1="a" kJ·mol-1
(2)2H2(g)+O2(g)===2H2O(g) △H2="b" kJ·mol-1
(3)H2(g)+1/2O2(g)===H2O(l) △H3="c" kJ·mol-1
(4)2H2(g)+O2(g)===2H2O(l) △H4="d" kJ·mol-1
下列关系式中正确的是:( )
| A.a<c<0 | B.b>d>0 | C.2a="b<0" | D.2c=d>0 |
SF6是一种优良的绝缘气体,分子结构中只存在S-F键。已知:1molS(s)转化为气态硫原子吸收能量280kJ,断裂1molF-F 、S-F键需吸收的能量分别为160kJ、330kJ。则S(s)+3F2(g)=SF6(g)的反应热△H为( )
| A.-1780kJ/mo | B.-1220 kJ/mol |
| C.-450 kJ/mol | D.+430 kJ/mol |
已知下列数据:
Fe(s)+O2(g) =FeO(s) △H=-272kJ·mol-1
2Al (s)+O2(g) =Al2O3(s) △H=-1675kJ·mol-1
则2Al(s) +3FeO(s) =Al2O3(s) + 3Fe(s)的△H是( )
| A.+859 kJ·mol-1 | B.-859 kJ·mol-1 |
| C.-1403 kJ·mol-1 | D.-2491 kJ·mol-1 |