* not completed

. How are the E-H bond strengths changing in s- and p-block?

The E-H bond strengths increase down each group in s- and p-block. correct incorrect

The E-H bond strengths decrease down each group in s- and p-block. correct incorrect

The E-H bond strengths remain almost constant down each group in s- and p-block. correct incorrect

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. In the coal gasification reaction, water vapour is allowed to react with __________ to produce hydrogen on a large scale:

CH₄ correct incorrect

C correct incorrect

CO correct incorrect

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. The reasons for the relatively low reactivity of H₂ are:

high bond enthalpy, high activation energy correct incorrect

high bond enthalpy, low activation energy correct incorrect

low bond enthalpy, low activation energy correct incorrect

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. Identify the incorrect statement:

Molecular hydrogen is activated by dissociation on a metal surface or formation of a metal complex. correct incorrect

Reactions between hydrogen and oxygen or halogens are typically free radical chain reactions. correct incorrect

Reactions involving hydrogen are rapid under ordinary conditions. correct incorrect

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. Hydrogen forms ___________ with the great majority of elements from groups 13–17.

molecular hydrides correct incorrect

metallic hydrides correct incorrect

saline hydrides correct incorrect

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. What are the products formed when a saline hydride (such as NaH) reacts with water?

metal oxide and hydrogen gas correct incorrect

metal hydroxide and oxygen gas correct incorrect

metal hydroxide and hydrogen gas correct incorrect

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. Hydrogen forms metallic hydrides with elements from groups:

13–17 correct incorrect

3, 4, 5 correct incorrect

1 and 2 correct incorrect

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. The following is not an example of the hydrogen bond:

B–H–B correct incorrect

N–H^…N correct incorrect

O–H^…O correct incorrect

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. Binary hydrogen compounds can be synthesized by all of the following reactions except:

direct combination of hydrogen with an element correct incorrect

metathesis of a halide (or a pseudohalide) with a hydride correct incorrect

an acid/base reaction between water and a Brønsted-Lowry acid correct incorrect

* not completed

. What are the characteristics of H^– as a ligand in d-block complexes?

H^– is a very polarizable, soft, two-electron σ donor ligand. correct incorrect

H^– has a high polarization power; it is soft, two-electron σ donor ligand correct incorrect

H^– is a mildly polarizable, hard, two-electron π donor ligand. correct incorrect