All Italian "h", which aren't simple graphic signs (ch, gh, sch) are silent; "io" is a hiatus, not a diphthong.
You should hear something like /'io'ɔ/, by the way the two "o" have a different sound (the 1st is closed, the 2nd is open), so, if well pronunced, you should distinguish the difference.

I might add that the "h" is silent in this case, so you are really saying "io - o". By the nature of those two words, they are going to run together! In italian, the word "ho", regardless of its placement, has a silent "h". For instance "Ho fame" (i'm hungry) is pronounced something like "oh fah-may" 

But yes, most romance languages do make a point to structure things in a way that makes things flow together nicely - precisely why we contract things in french and even change them completely to make them sound better sometimes! For instance, in french, "Je peux" means "I can", but if you were to invert it to ask a question "can i..." it changes to "Puis-je..." because "peux-je" sounds bad hahah

In Italian, if the same sound is at the end of one word and the beginning of the next, they run together as a single sound and single syllable. It helps sentences flow more smoothly, and the same thing happens in Spanish and French.

In Spanish, when you say "de esperanza" (of hope), it sounds like desperanza. The two 'e's combine into one sound. 

In French, instead of saying, "la anniversaire" (the anniversary or birthday), you say "l'anniversaire". 

You sometimes see it written with apostrophes, such as the French example above or in Italian, instead of "la industria", you say "l'industria". In Spanish, the same thing happens, but there are no apostrophes. De+el=del A+el=al. You hear it in English, too. We+are=We're.