Answer:
Covalent Bond
Explanation:
In the diagram Carbon and each of the 4 Hydrogens are sharing electrons. They are also both non metals. Both of these are characteristics of Covalent Bonds.
Answer:
The surface tension of the water
Explanation:
The surface of the water curves down twords the edge of the coin.
Answer no 1)
The correct option is A) He did not try to learn it. It was natural.
As Sergei did not put any effort in learning the art of tongue rolling, hence we can assume that this characteristic was found to be naturally present in Sergei. This hence shows that Sergei has acquired the characteristic of tongue rolling through inheritance.
Answer No 2)
We can learn whether other persons in the class have the characteristic of tongue rolling or not by observing them. In the students who can roll their tongue we can conduct a survey asking them whether they tried to learn the trait or did not put any effort to learn tongue rolling. The students who learned the skill by practicing might have acquired the characteristic from learning.
Answer No 3)
We can survey the class for features like eye color, hair color, height, weight. We can ask certain questions in our survey like whether the characteristic can be seen in either the mother, father or other siblings.
Answer:
The correct answer is - the number of days the rainwater stands in the jars.
Explanation:
The independent variable or the manipulating variable is a variable in a research or study is the variable which affects the dependent variable or the variable that is going to measure in the study.
In the study, variables that recieves the treatment and changed in every subject are independent variables and in this study number of days the rainwater standing in various jars that might affect the growth of the bacteria in rainwater.
1 CH4 (g) + 2 O2 (g) -----> CO2 (g) + 2H2O(l) ΔH= - 890 kJ
1 mol 2 mol
1) If ΔH has minus, it means "release". We need only "release" choices.<span>
2) From reaction
1 mol </span>CH4 (g) "releases" ΔH= - 890 kJ - We do not have this choice.
2 mol O2 (g) "release" ΔH= - 890 kJ, so
1 mol O2 (g) "release" ΔH= - 445 kJ
Correct answer is B.
