The human brain recognises shapes first, then colour – so before your potential customer has even read anything about you there is already a preconception. Obviously this is not an exact science and the individual’s personal upbringing will influence them. Colours have different cultural meanings too, so be mindful. If this is something you want to know more about, here’s a great piece on hubspot
As part of your brand guidelines there should be a breakdown of your colours which will reproduce as close to the desired colour as possible i.e. CMYK, RGB, HEX, PMS and so on. Make sure you test it on various media before signing it off. Ideally you should also consider a secondary palette which will compliment your brand colours and also investigate what a tint of your brand colours would look like.