Give me number of significant figures in the number 40

If a light bulb is missing or Broken in a parallel circuit, will the other bulb light

Calculate the amount of CuSO4•5H2O required to make 25 mL of a 0.45 M solution of CuSO4.

My question is, that it's asking us to tell whether the partial pressure of a molecule will increase decrease of remain the same and to show it by a calculation? I don't which calculation to use. I have V T P and grams.

if you weigh the lauric acid to the nearest 0.1g and you weigh the unknown solid to the nearest 0.0001g, can you calculate a molar mass of your unknown solid to three significant figures? Show clearly your reasoning.

Which of the following is an example of chemistry research in the main area of energy?. a. producing bioplastics. b. specific reactions between prescription drugs and chemicals in cells. c. developing rechargeable batteries. d.

What element is represented by the following electron configuration: 1s22s22p63s23p64s23d4 Question 2 options: Cr Ca Ge Ar

He substance, cocl2, is useful as a humidity indicator because it changes from pale blue to pink as it gains water from moist air. What is its name?

The weighted average atomic mass of an element depends upon the a. relative abundance of protons in the element b. mass and relative abundance of each isotope of that element c. mass and relative abundance of each neutron of that element d.

What part of an atom do we change for isotopes

The Safe Drinking Water Act (SDWA) sets a limit for mercury-a toxin to the central nervous system-at 0.002 mg/L. Water suppliers must periodically test their water to ensure that mercury levels do not exceed 0.002 mg/L.