配制250ml1mol/LH2SO4溶液所要用的溶解仪器是______,定容仪器

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问题:

配制250ml1mol/LH2SO4溶液所要用的溶解仪器是______,定容仪器是______,用于引流的是______,用于加水使溶液的凹液面跟刻度线相切的是______.

考点:配制一定物质的量浓度的溶液
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一般认为流通加工属于______环节。

A.生产

B.交换

C.分配(流通)

D.消费

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M型超声是指()

A.振幅调制型

B.辉度调制型

C.彩色血流显像

D.多普勒频谱显示

E.以上都不是

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依据《安全生产许可证条例》的规定,对已经进行生产的企业,规定应当在本条例施行之日起()年内依法向安全生产许可证颁发管理机关申请办理安全生产许可证。

A.1

B.2

C.3

D.4

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Melissa and LoveLetter made use of the trust that exists between friends or colleagues. Imagine receiving an (71) from a friend who asks you to open it. This is what happens with Melissa and several other similar email (72) . Upon running, such worms usually proceed to send themselves out to email addresses from the victim’s address book, previous emails, web pages (73) .
As administrators seek to block dangerous email attachments through the recognition of well-known (74) , virus writers use other extensions to circumvent such protection. Executable (.exe) files are renamed to .bat and .cmd plus a whole list of other extensions and will still run and successfully infect target users.
Frequently, hackers try to penetrate networks by sending an attachment that looks like a flash movie, which, while displaying some cute animation, simultaneously runs commands in the background to steal your passwords and give the (75) access to your network.

A.attachment

B.packet

C.datagram

D.message

题型:填空题

水蒸汽蒸馏的原理是什么?

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