Hello,
I think the answer is B) It is second longest river in south america
Hope this helps!!
~Girlygir101~
Answer:
1.09 M
Explanation:
Let's define the equation that will be used to calculate the final concentration of the resultant calcium nitrate solution. In order to calculate it, we need to find the total number of moles of calcium nitrate and divide by the total volume of the resultant solution:

This equation firstly helps us find the number of moles of calcium nitrate. Multiplying molarity by volume will yield the moles. Adding the moles from the first component to the second component will provide us with the total number of moles of calcium nitrate:

Now, the total volume of this solution can be found by adding the volume values of each component:

Finally, dividing the moles found by the total volume will yield the final molarity:

Answer:
The elements become less reactive.
Explanation:
As we move from left to right across the periodic table the number of valance electrons in an atom increase. The atomic size tend to decrease in same period of periodic table because the electrons are added with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. The positive charge is going to increase and this charge is greater in effect than the charge of electrons. This effect lead to the greater nuclear attraction and reactivity increases because of greater electron affinity.
As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased. The electron affinity decreases because of shielding effect and thus atom become less reactive.
Answer:

Explanation:
Hello,
In this case, since the undergoing chemical reaction is:

The corresponding moles of carbon dioxide occupying 40.0 mL (0.0400 L) are computed by using the ideal gas equation at 273.15 K and 1.00 atm (STP) as follows:

Then, since the mole ratio between carbon dioxide and calcium carbonate is 1:1 and the molar mass of the reactant is 100 g/mol, the mass that yields such volume turns out:

Regards.
The correct Answer for this question is D