The first element discovered through synthesis was technetium<span>—its discovery being definitely confirmed in 1936. Hope that helps.</span>
Answer:
0.00471 grams H₂O
Explanation:
To determine the mass, you need to use the following equation:
Q = mcΔT
In this equation,
-----> Q = energy/heat (J)
-----> m = mass (g)
-----> c = specific heat capacity (J/g°C)
-----> ΔT = temperature change (°C)
The specific heat capacity of water is 4182 J/g°C. You can plug the given values into the equation and simplify to isolate "c".
Q = 0.709 J c = 4182 J/g°C
m = ? g ΔT = 0.036 °C
Q = mcΔT <----- Equation
0.709 J = m(4182 J/g°C)(0.036 °C) <----- Insert values
0.709 J = m(150.552) <----- Multiply 4182 and 0.036
0.00471 = m <----- Divide both sides by 150.552
Answer:
This means that the isotope of silicon with a mass number of 28 is by far the most common of these three isotopes.
Explanation:
The abundance of Si-28 is 92.23%. Si-29 is 4.68% and Si-30 is 3.09%.
Because most Si atoms have a mass of 28 amu, the average mass of all silicon atoms is very close to 28.
Here is a video which summarizes how to calculate average atomic mass from data about mass and relative abundance.
Answer:

In which [Ag+] in negligibly small and the concentration of each reactant is 1.0 M
The answer is A) PO43- < NO3- < Na+
Explanation:
Ag+ is removed from the solution just like PO43-, so there are just 2 possible answers at this point: a or b. Then we can notice that Na3PO4 releases 3 moles of Na+ and just 1 mole of NO3-
We have 100mL of each reactant with the same concentration for both (1.0 M) so:
(0.1)(1)(3)= 0.3 mol Na+
(0.1)(1)= 0.1 mol NO3-
so PO43- < NO3- < Na+