Answer:
I think a tell me if I am wrong
Answer:
A. Helium
Explanation:
In chemistry, a noble gas refers to a group of elements placed in group 18, which is located in the last column from left to right in the periodic table. Additionally, these elements are defined by their low reactivity, also as gases, they do not have color or odor. Helium is part of this group that contains other 5 elements because Helium characteristics are similar to other noble gases, indeed this is the first noble gas in the periodic table. Additionally, helium is an abundant element found in all the universe especially in stars. Thus, the element that is a noble gas is Helium.
Answer:
376.56
Explanation:
using the formula q=mcΔT, where m=15g, C=4.18J/g°C and ΔT=6.0°C
1) Use of density formula to calculate mass of sample, M
D = M / V => M = D* V = 0.9977 g / mL * 50.00 mL = 49.885 g of sample
Realize that the sample is the solution.
2) Use ppm concentration to calculate mass of solute (calcium carbonate)
By definition, 75.0 ppm = 75.0 g of calcium carbonate / 1,000,000 g of solution.
You use that ratio to calculate the mass of calcium carbonate in 49.885 g of solution.
Mass of solute = 49.885 g of solution * [75.0 g of calcium carbonate] / [1,000,000 g of solution] =
Mass of solute = 0.00374 g of calcium carbonate
Answer: 0.00374 g of calcium carbonate
Answer:
6
Explanation:
As , 2H2 + O2 = 2H2O
with 6 H2, 4O2 is excess.
H2O molecules formed = 6