两个氘核聚变产生一个中子和一个氦核，已知氘核质量为2.0136u，_爱下问搜题

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问题问答题

两个氘核聚变产生一个中子和一个氦核，已知氘核质量为2.0136u，氦核质量为3.0150u，中子质量为1.0087u，则

（1）写出核反应方程；

（2）算出释放核能；

（3）若反应前两个氘核的功能均为0.355MeV，反应时发生的是正对撞，设反应后释放的核能全部转化为动能，则反应后氦核与中子的动能各为多大？

答案

(1) H+H→He+n (2) △E=0.0035×931.5MeV=3.26MeV (3) =2.97MeV=0.99MeV

核反应中释放的能量可由爱因斯坦方程先计算出质量亏损后进而求得。

（1）核反应方程为 H+H→He+n

（2）质量亏损为

△m=2×2.0136―1.0087―3.0150

=0.0035（u）

而对应于1u的质量亏损，释放的核能为931.5MeV，于是上述核反应中释放的能量为

△E=0.0035×931.5MeV=3.26MeV

（3）设氘核H，氦核He，中子n的质量数分别为m、m₁、m₂，于是有

mσ－mσ=m₁σ₁－m₂σ₂

mσ²=E_k=0.35MeV

m₁σ=

m₂σ=

2E_k+△E=+

由此解得

=2.97MeV

=0.99MeV

完形填空

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单项选择题 B1型题

损伤与风湿兼证者（）。

A.坚骨壮筋膏

B.狗皮膏

C.万灵膏

D.化坚膏

E.太乙膏