There are many Quranic verses which deal with hypocrites. In the light of those verses one can realize who the hypocrites are and what constitutes their distinct attitudes and behavioral indexes. In the below, I will have a cursory look at some of the Quranic verses related to hypocrites and their behavioral indexes through which you can better recognize them.
Anyhow, hypocrite, literally talking, is defined as someone who pretends to have certain beliefs or opinions that he does not really have. Some of the hypocrites’ behavioral attitudes are as following:
The hypocrites pretend to believe in any creed or religion but their hearts are devoid of faith. Thus Allah, the Almighty, says:
وَ إِذا جاؤُكُمْ قالُوا آمَنَّا وَ قَدْ دَخَلُوا بِالْكُفْرِ وَ هُمْ قَدْ خَرَجُوا بِهِ وَ اللَّهُ أَعْلَمُ بِما كانُوا يَكْتُمُونَ
When they come to you, they say," We believe." Certainly they enter with disbelief and leave with it, and Allah knows best as to what they have been concealing. (Chapter Maidah/61).
Moreover, when they meet the faithful, they say," We believe," but when they are alone with their devils, they say," We are with you; we were only [deriding] them. It is Allah who derides them, and leaves them bewildered in their rebellion (Chapter al-Baqarah, 14-15)
2. Betrayal and Disloyalty
Hypocrites are in constant hesitations and fluctuations. They always live between belief and disbelief. They do not remain in one state or condition.
They betray their partners making no difference whether their partners are believers or disbelievers. Since they wander in bewilderment and break their promises, no one can trust them. Due to their lack of commitment, no one count on them. So, the hypocrites, due to their constant betrayal, can never be good partners not only for the believers but also for the disbelievers. Thus Allah says:
مُّذَبْذَبِينَ بَيْنَ ذَلِكَ لاَ إِلَى هَؤُلاء وَلاَ إِلَى هَؤُلاء وَمَن يُضْلِلِ اللّهُ فَلَن تَجِدَ لَهُ سَبِيلاً
(the hypocrites are) wavering in between: neither with these nor with those. And whomever Allah leads astray, you will never find any way for him (Chapter al-Nisa/143).
3. They enjoin bad and forbid good
In the Islamic literature and atmosphere, the community is called upon to ensure that justice is maintained and injustice avoided. This responsibility functions through the institution of “enjoining what is right and forbidding what is wrong” (alamr bi-l-marūf wa-l-nahy an al-munkar) and is regarded by the Qurān as essential to social cohesion. Therefore, all are required to remain committed to the very maxim but the hypocrites move against the motion. They commit evils and persuade others not to do good deeds. The Quran, describing their status, says:
الْمُنَافِقُونَ وَالْمُنَافِقَاتُ بَعْضُهُم مِّن بَعْضٍ يَأْمُرُونَ بِالْمُنكَرِ وَيَنْهَوْنَ عَنِ الْمَعْرُوفِ وَيَقْبِضُونَ أَيْدِيَهُمْ نَسُواْ اللّهَ فَنَسِيَهُمْ إِنَّ الْمُنَافِقِينَ هُمُ الْفَاسِقُونَ
The hypocrites, men and women, are all alike: they bid what is wrong and forbid what is right; and are tight-fisted. They have forgotten Allah, so He has forgotten them. The hypocrites are indeed the transgressors (Chapter Towbah /67).
4. Selling guidance in exchange for misguidance.
أُوْلَئِكَ الَّذِينَ اشْتَرُوُاْ الضَّلاَلَةَ بِالْهُدَى فَمَا رَبِحَت تِّجَارَتُهُمْ وَمَا كَانُواْ مُهْتَدِينَ
They are the ones who bought error for guidance, so their trade did not profit them, nor were they guided (Chapter al-Baqarah/16).
The hypocrites are friendless people both in this world and in the hereafter. In this world, no one can trust them and they will not enjoy good aftermath in the hereafter either because Allah, the Almighty, has promised them punishments severer than those of the arrogant disbelievers'. They are the practical examples of a proverb that says 'he who hesitates is lost'.
In respect with the second part of the question, it has to be briefly stated that every critical stance on Muslim Ummah is not and should not be considered as a hypocritical act. - Quora