1.单选题- (共9题)

A. 图a中火柴头垂直向上燃烧时容易填灭,是因为热空气增大了火柴梗的着火点
B. 图a中火柴头斜向下时更易燃烧,因为火柴梗不断被加热和受到热气流带来空气的助燃
C. 图b中蜡烛火焰很快熄灭,是因为金属丝圏吸收热量,温度降低到蜡烛着火点以下
D. 煤球制成蜂窝煤后燃烧更剧烈是因为增大了煤与氧气的接触面积
A.电器着火,迅速切断电源 |
B.沼气池清理作业前进行灯火试验 |
C.室内起火,迅速打开所有门窗通风 |
D.夜间发现液化气泄漏,开灯进行检查 |

A.该实验只能得出燃烧需要氧气这一结论 |
B.该实验使用了相同的可燃物 |
C.该实验现象是铜片上的白磷不燃烧,红磷燃烧 |
D.该实验说明燃烧需要达到可燃物的着火点 |

A.纸锅的着火点很高 |
B.面汤使纸锅的着火点升高了 |
C.面汤隔绝了氧气使纸锅不能燃烧 |
D.加热时面汤蒸发吸热使纸锅温度达不到其着火点 |
2.选择题- (共4题)
七选五
Nail-biting(咬指甲) is one of the most common annoying habits in children. {#blank#}1{#/blank#} But you needn't worry too much and as soon as you realize what's causing nail-biting, you can help your child overcome and stop it. So, here's what you can do about it.
{#blank#}2{#/blank#}In some cases, children won't even realize they are biting their nails, let alone know why they are doing it. So make sure you have a conversation with your child (if he/she is old enough) and make him/her realize he/she is doing it and try to figure out why it's happening.{#blank#}3{#/blank#} It's important to agree on the level of your involvement. If he/she wants help, create a secret reminder that will make him/her stop without embarrassing him/her.
Give alternatives (替代物).{#blank#}4{#/blank#} Depending on the age of the child, there are several things that you can offer such as a small ball, Play-Doh games, or any kind of other small toys.
Use bitter solutions(溶液). Forcing a child to keep this solution on his/her fingers may feel like a punishment.{#blank#}5{#/blank#} Everything else will only lead to embarrassment and discouragement. Furthermore, some of these solutions contain pepper which burns if it enters a child's mouth or eyes. But if you have an adolescent child who wants to quit biting his/her nails, you may suggest and try out this solution.
A.It's also likely to continue as the child grows up.
B.Help the child become aware of the habit.
C.You should also consider asking for professional help.
D.Make an agreement on how you're going to stop it together.
E.The best thing children can do is communicate with their parents.
F.The child needs to go through the process painlessly and in agreement with you.
G.That will keep his/her hands occupied when he/she is likely to bite his/her nails.
七选五
Nail-biting(咬指甲) is one of the most common annoying habits in children. {#blank#}1{#/blank#} But you needn't worry too much and as soon as you realize what's causing nail-biting, you can help your child overcome and stop it. So, here's what you can do about it.
{#blank#}2{#/blank#}In some cases, children won't even realize they are biting their nails, let alone know why they are doing it. So make sure you have a conversation with your child (if he/she is old enough) and make him/her realize he/she is doing it and try to figure out why it's happening.{#blank#}3{#/blank#} It's important to agree on the level of your involvement. If he/she wants help, create a secret reminder that will make him/her stop without embarrassing him/her.
Give alternatives (替代物).{#blank#}4{#/blank#} Depending on the age of the child, there are several things that you can offer such as a small ball, Play-Doh games, or any kind of other small toys.
Use bitter solutions(溶液). Forcing a child to keep this solution on his/her fingers may feel like a punishment.{#blank#}5{#/blank#} Everything else will only lead to embarrassment and discouragement. Furthermore, some of these solutions contain pepper which burns if it enters a child's mouth or eyes. But if you have an adolescent child who wants to quit biting his/her nails, you may suggest and try out this solution.
A.It's also likely to continue as the child grows up.
B.Help the child become aware of the habit.
C.You should also consider asking for professional help.
D.Make an agreement on how you're going to stop it together.
E.The best thing children can do is communicate with their parents.
F.The child needs to go through the process painlessly and in agreement with you.
G.That will keep his/her hands occupied when he/she is likely to bite his/her nails.
3.多选题- (共1题)

A.发生燃爆后体系的温度升高,氧气耗尽蜡烛熄灭 |
B.蜡烛熄灭时因为蜡烛的着火点改变了 |
C.在有限的作业空间,可燃性粉尘遇明火一定会发生燃爆 |
D.实验用的容器可用废旧矿泉水瓶,但不能用玻璃瓶 |
4.填空题- (共6题)
(1)干粉灭火器,除可用来扑灭一般失火外,还可用来扑灭___________等燃烧引起的失火;
(2)二氧化碳灭火器,可用来扑灭_______、_______、贵重设备、精密仪器等引起的失火;
(3)____________灭火器,可用来扑灭非水溶性可燃性液体,如_______、_______等以及固体材料,如_______、_______等引起的失火。
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【1】题量占比
单选题:(9道)
选择题:(4道)
多选题:(1道)
填空题:(6道)
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【2】:难度分析
1星难题:0
2星难题:0
3星难题:0
4星难题:1
5星难题:0
6星难题:6
7星难题:0
8星难题:9
9星难题:0