Organic Chemistry question

[NatashaColorado]

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I was practicing O Chem today, from Kaplan's MCAT books, and one question had an unexpected answer... Am I missing something or the book is wrong?
Question: What type of hybridization does Be atome have in BeH2 compound?
a. sp
b. sp2
c.sp3
d. none of the above.
My answer was "none of the above", because I figured, Be only had 1s and 2s orbitals, H has 1s orbital - there is no p orbital anywhere. To my surprise, the correct answer was a. sp ?! And the reason book gave is "BeH2 molecule is linear and since only sp orbitals are oriented at the angle of 180 degree, the Be atome is sp hybridized" - quoted.
No way! Makes no sense that atom with no p orbital would be hybridized at all!
What do you, guys, think?

 

[hurricaneuro]

Basic periodic table knowledge. Be has two valence electrons...and two H's...so Be H2 is linear. There are no lone pairs.

 

[KHE]

Basic periodic table knowledge. Be has two valence electrons...and two H's...so Be H2 is linear. There are no lone pairs.

lol

Even though most of of my knowledge on this topic has looong been expunged from my memory, when you're taking these types of multiple choice tests, the answer is almost NEVER "none of the above."

 

[NatashaColorado]

Basic periodic table knowledge. Be has two valence electrons...and two H's...so Be H2 is linear. There are no lone pairs.

Right. So, what type of hybridization does Be atom have? sp hybridization is not possible in BeH2 (hybridization concept doesn't apply without p orbitals presence), so why is a. the right answer?

 

[NatashaColorado]

lol

Even though most of of my knowledge on this topic has looong been expunged from my memory, when you're taking these types of multiple choice tests, the answer is almost NEVER "none of the above."

It would be great to know it for sure - I hate "none of the above" answers!

 

[CielloStelatto]

since it already has a full s orbital, it can't make s bonds like H2 can. Instead it bumps an e up to p so it can bond. see this: http://library.thinkquest.org/15567/lessons/10.html