<span>A supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.</span>
Answer:
NH₃
Explanation:
The hydrogen bond is a specially strong type of dipole-dipole interaction. For a hydrogen bond to occur, a molecule must have a hydrogen atom and a very electronegative atom, such as nitrogen, oxygen or fluorine. The hydrogen atom has a positive charge density while the heteroatom has a negative charge density.
<em>Which of the following molecules can form hydrogen bonds? </em>
NH₃ YES
NaH NO
HI NO
BH₃ NO
CH₄ NO
In 1871, a Russian Chemist, Dimitri Mendeleev, gave a useful scheme for classification of elements. He presented the first regular periodic table in which elements of similar chemical properties were arranged in eight vertical columns called groups. The horizontal rows of table were called periods. He arranged elements in ascending order of their atomic masses and found that elements having similar chemical properties appeared at regular intervals. This observation was called Periodic Law.
Answer:
False
Explanation: The wind's direction is shown by a long shaft. it will point to the direction from which direction the wind is blowing.