the two white genes are completely separate, nothing to do with each other. rw is always rw, dw is always dw. like a white jeep remains a jeep even if you get a white porsche and have both at same time. they are a jeep and a porsche even if they are the same color visually.. the machinery is different.
yes exactly, a rw chick had parents with the rw gene. it will always be rw. rw bred to rw always 100% rw, so a white silkie bred to white silkie will always produce all white silkies. no other color at all.
all white silkies are recessive white.. because rw does not interfere with skin pigmentation. dw does, and it is very hard to keep black skin on birds with dw because it blocks pigment in both feathers and skin. (understand, this is omitting the paint silkies.. not sure if anybody has figured their genetics yet & they are very new)
the term 'recessive' you can sort of think of it being 'weak' and have to be in 'pure form to show up visually'.
as for 'dominant' think of it as 'strong, shows up visually in crosses'.
for example:
rw bred to black chicken- all black chicks. (this white is "weak")
dw bred to black chicken- all white chicks. (its dominant personality says 'i am here!') your chick is an example of this.