B) hydrogen gas burns in air.
explanation: the rest are physical properties.
The heat cause 300g water temperature increase from 20 to 26 celcius. The heat transferred would be: 300g * (26 °C -20 °C) *4.2 joule/gram °C= 7560J
The unknown substance is added to the water, so its final temperature should be the same as the water. The calculation would be:
7560J= 124g * (100-26)* specific heat
specific heat= 7560J / 124g / 74 °C= 0.8238 J/gram °C
The total number of elements that one particular element can bond to can be determined by simply drawing the Lewis structure of the element.
Place the chemical symbol
Then look at the group number = valence electrons
Distribute the valence electrons around the atom.
C = 4 bonds
N = 3 bonds
O = 2 bonds
Answer:
B. flourine
Flourine is the 9th element in the periodic table