Some physical evidence was obtained from a crime scene. For which of these pieces of evidence will forensic scientists conduct an identification test?

A.

a hair strand

B.

a black powder

C.

a glove

D.

bloodstains

When are reactions always spontaneous?

Gastric juice in the stomach contains pepsin and sulfuric acid. TrueFalse

Question 1 how much water would you add to 175 ml of 6.00 m hydrochloric acid to prepare a 2.00 m solution of this acid? 350 ml 700. ml 58.3 ml 525 ml none of the above

Assuming that pressure and temperature are constant, how many liters of oxygen gas will be required to produce 0.160 L of nitrogen gas. 4 NH3 (g) + 3 O2 (g) → 6 H2O (g) + 2 N2 (g)

What tool would you use to measure volume

Why does copper give off blue light and lithium give off red light?

Calculate the number of atoms in a 1.26*103 g sample of silicon.

Which of these actions a sustainable practice? A. Expanding the amount of fossil fuels extracted B. Setting usage limits on a resource C. Overconsuming a resource D. Exceeding fossil fuel emissions targets

The activation energy for the isomerization ol cyclopropane to propene is 274 kJ/mol. By what factor does the rate of this reaction increase as the temperature rises from 231 to 293 oC?

Why is it important for scientist to review and repeat the work of other scientists?