A scientist carried out several different procedures, each of which caused a change in matter. Select each procedure that is likely a chemical change.
Salt crystals were crushed into a fine powder.
оос
Bubbles were produced when iron was placed in acid.
Two liquids were combined, and a solid appeared.
A piece of metal melted when it was heated.
OO
A white substance turned blue when water was added.
Reset
Next

Select the correct answer from each drop-down menu. daniel and sanya are scientists. daniel is studying whether the increasing frequency of tropical storms is affecting coastal erosion. sanya is investigating whether the discharge from industrial plants has any impact on the ph concentration of freshwater swamps in the surrounding area. which fields of science are daniel’s and sanya’s studies most closely related to? daniel’s field of study is related to science, and sanya’s field of study is related to .

Apeak with a retention time of 407 s has a width at half-height (w1/2) of 7.6 s. a neighboring peak is eluted 17 s later with a w1/2 of 9.4 s. a compound that is known not to be retained was eluted in 2.5 s. the peaks are not baseline resolved. how many theoretical plates would be needed to achieve a resolution of 1.5?

2. you__turn left on a red light if you are in the left-most lane of a one-way street, you're turning into the left-most lane of a one-way street, and no nearby sign prohibits the turn.