Answer:
PHYSICS.
Explanation:
BLUE BOX CA BE REFERRED AS AN ELECTRONIC DEVICE WHICH IS USED IN THE TELEPHONIC CIRCIUTSTI PASS ON LONG DIATANT SIGNALS.
Atomic number = 42
Name = Molybdenum
Atomic symbol = Mo
Group number = VI(B)6
Mo = Metal
How to find all valves of Z=42?
Here, we are going to find out the name, symbol and group numbers element with the following Z value and their classification as a metal, metalloid, or nonmetal.
The atomic number of the element is 42
Therefore, the name of the element is Molybdenum
The atomic symbol of the element is Mo
The group number of is VI(B)6
Mo is a metal
Hence, the element is Molybdenum
Learn more about atomic symbol here :
brainly.com/question/930789
#SPJ4
Answer:
Exothermic reaction: In exothermic reaction, energy is transferred to the surroundings, and the surrounding temperature increases, this is known as exothermic reaction. In other words energy exits in exothermic reaction. Some example of exothermic reactions are:
1) Neutralisation reaction.
2) Combustion reaction.
3) Some oxidation reaction.
Endothermic reaction: In endothermic reaction, energy is taken in from the surrounding, and the surrounding temperature decreases, this is known as endothermic reaction. In other words energy enters in endothermic reaction. Some example of exothermic reactions are:
1) Thermal decomposition.
2) Reaction between citric acid and sodium hydrogen carbonate.
Answer:
yo gotta be more specific
Complete Question:
A chemist adds 55.0 mL of a 1.1M barium acetate (Ba(C2H3O2)2) solution to a reaction flask. Calculate the mass in grams of barium acetate the chemist has added to the flask. Round your answer to 2 significant digits.
Answer:
15 g
Explanation:
The concentration of the barium acetate is given in mol/L (M), thus, the number of moles (n) of it is the concentrantion multiplied by the volume (55.0 mL = 0.055 L):
n = 1.1 * 0.055
n = 0.0605 mol
The molar mass of the substance can be calculated by the sum of the molar mass of each element, which can be found at the periodic table. Thus:
Ba = 137.33 g/mol
C = 12.00 g/mol
H = 1.00 g/mol
O = 16.00 g/mol
Ba(C2H3O2)2 = 137.33 + 4*12 + 6*1 + 4*16 = 255.33 g/mol
The molar mass is the mass divided by the number of moles, thus the mass (m) is the molar mass multiplied by the number of moles.
m = 255.33 * 0.0605
m = 15.45 g
Rounded by 2 significant digits, m = 15 g.
