Answer:
The correct order it b. always add acid last.
Explanation:
Adding acid first could result on a violent reaction and heat or fumes can be generated. The best approach is to always add all the water or non-acid component first, or add a significant portion before adding the acid slowly to the mixture.
Answer:
The balanced chemical reaction is given as:

Explanation:
When aqueous cesium sulfate and aqueous barium perchlorate are mixed together it gives white precipitate barium sulfate and aqueous solution od cesium perchlorate.
The balanced chemical reaction is given as:

According to reaction, 1 mole of cesium sulfate reacts with 1 mole of barium perchlorate to give 1 mole of a white precipitate of barium sulfate and 2 moles of cesium perchlorate.
Cause it felt like being cold
Answer:
hello your question is incomplete the options are missing
Determine the resultant velocity for the plane when it is travelling
i) To the east
ii) To the west
answer :i) 270 i
ii) -150 i
Explanation:
velocity of Airplane = 210 m/s
wind velocity = 60 m/s to the east
The resultant velocity for the plane when it is travelling
let the velocity of the wind = V2
velocity of the plane = v1
i) The resultant velocity for the plane when travelling to the east
Vr = V2 i + V1 i
Vr= 60i + 210i = 270i
ii) resultant velocity when the plane is travelling to the west
Vr = - V1 i + V2i
= -210i + 60 i = -150 i