Suppose a laboratory has a 38 g sample of polonium-210. the half-life of polonium-210 is about 138 days.

a. how many half-lives of polonium-210 occur in 1104 days?

b. how much polonium is in the sample 1104 days later?

Given the balanced equation: I2 (s) + energy = = > I2 (g) As a sample of I2 (s) sublimes to I2 (g), the entropy of the sample (1) increases because the particles are less randomly arranged (2) increases because the particles are more randomly

All atoms have molecules and mass so are therefore

For an atoms electrons, how many energy sub levels are present in the principal energy level n=4? A. 4 B. 9 C. 10 D. 16 E. 32

You make the following measurements of an object - 22 kg and 42 m3. What would the object's density be? Show your work for credit and include final units.

Can someone explain to me what the element Americium is?

How many moles are in 10 grams of CaCl2?

Which is the correct formula for phosphorus pentachloride? PCl4 because a subscript of 4 indicates four Cl atoms PCl5 because a subscript of 5 indicates five Cl atoms P5Cl because a subscript of 5 indicates five P atoms P5Cl3 because a subscript of

Why are the elements in groups 3 to 12 often used to make dyes?

What is not needed for corrosion of metals? a. oxygen c. water b. ions d. sunlight

What force can move the oceans