看到抢险队员在冰雪覆盖的道路上洒大量的盐，小明同学产生疑问：_爱下问搜题

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问题填空题

看到抢险队员在冰雪覆盖的道路上洒大量的盐，小明同学产生疑问：含盐浓度不同的冰，熔化特点有无区别？为此，小明同学用纯水、淡盐水、浓盐水制得质量均为lkg的纯冰、淡盐冰、浓盐冰，在相同加热条件下测量三者的温度变化，并得到三条温度变化曲线（纯冰对应曲线①、淡盐冰对应曲线②、浓盐冰对应曲线③），如图所示．根据曲线图可知，含盐浓度越高的冰，比热容越______（选填“大”或“小”），熔化前升温越______（选填“快”或“慢”），并能在更______（选填“高”或“低”）的温度熔化．

答案

根据曲线图可知：质量相同的三种物质升高相同的温度，浓盐冰的加热时间最短，吸收的热量最少；

根据公式Q_吸=cm（t-t₀）得：质量、升高的温度一定时，吸收的热量和物质的比热容成正比，浓盐冰吸收的热量少说明它的比热容小．

在三种物质都未熔化前取升高相同的温度，可以看出浓盐冰对应曲线加热时间最短，所以含盐浓度越高的冰熔化前升温越快．

因为晶体在熔化时吸收热量，温度保持不变，所以由图象知含盐浓度越高的冰，能在更低的温度熔化．

故答案为：小，快，低．

完形填空

Birthdays often bring surprises. But this year’s surprise on the birthday of the great British playwright William Shakespeare is __21__ one of the most surprising.
On April 22, one day before his 441^st birthday anniversary, experts __22__ that one of the most recognizable __23__ of William Shakespeare is a fake (赝品).
This __24__ that we no longer have a good __25__ of what Shakespeare looked like. “It’s very possible that many pictures of Shakespeare are unreliable because many of them are __26__ of this one,” said an expert from Britain’s National Portrait Gallery.
The _27_ comes after four months of testing. Experts from the gallery say the image — commonly known as the “Flower portrait” — was actually __28__ in the 1800s, two centuries __29_ Shakespeare’s death.
The art experts who work at the gallery say they used modern chemistry technology to __30__ the paint on the picture. These checks found traces (痕迹) of paint deep in the picture __31__ about 1814.
Shakespeare __32__ in 1616, and the date that appears on the portrait is 1609.
“We now think the portrait dates back to around 1818 to 1840. This was __33__ there was a new interest in Shakespeare’s__ 34__ ,” Tanya Cooper, the gallery’s 16^th century curator (馆长) said.
The __35__ picture has often been used as a cover for __36__ of his plays. It is called the “Flower portrait” because one of its __37__, Desmond Flower, gave it to the Royal Shakespeare Company.
“There have always been __38__ about the authenticity (真实性) of the painting,” said David Howells, curator for the Royal Shakespeare Company.
“Now we know the truth, we can put the image in its proper place in the history of Shakespearean portraiture (画像技法),” he said.
Two other images of Shakespeare are also being studied as part of the investigation and the results will __39__later in May. But for now what Shakespeare really looked like will remain a __40__.

B．masterpieces

B．productions

A．looking back

B．dating from

C．getting along

D．starting with

A．requirements

B．collections

C．consequences

D．playwrights

多项选择题

脚手架的防电要求（）：

A.包扎隔绝

B.接地处理

C.接零