Answer:
the independent variable (sometimes known as the manipulated variable )
Explanation:
is the variable whose change isn't affected by any other variable in the experiment
The
combustion of heptane (C7H16) in oxygen spontaneously occurs. The products of
the reaction are carbon dioxide and water vapor. The balanced chemical equation
is 7H16 + 11O2 → 7CO2 + 8H2O H
= –2877.5 kJ.
2) D = m/V. Knowns: V = (4 x 4 x 4) = (64) D = 2.7
2.7 = m/(64)
172.8 = m or with significant figures, 170
3) Knowing the model of the atom is crucial becuase without understanding what everything is made up of, then there is no way of telling how it is going to react with outside things. Knowing the model of the atom can better help us visualize what it looks like and it can also tell us how it is going to react baced on its propertys and what it is made of.
4) Dalton's theory tells us that 1, all matter is made of atoms, which are indivisible and indestructiable. This does not agree with todays findings because we know that atoms can be broken up into sub atomic particals, and even those sub atomic particals can be broken down even further to sub-sub-atomic particals such as quarks and borons. 2, We also know about Isotopes. Isotopes are the same atom but with different atomic weights becaus of the amount of nutrons in the nuclei.
5) If an element has 12 protons and 17 neutron, in order to be stable and found in nature, the atom must have 12 protons because protons are positive and neutrons have a charge of 0 so in order to balence the atom out, the electrons, with a negitive charge, must be the same number as the protons.
We know that the relationship between enthalpy and entropy is:
ΔS = <span>ΔH/T
Therefore, both the change in enthalpy and the change in entropy will have the same sign. Now, considering each change:
Sublimation: Negative
Freezing: Positive
Condensation: Positive
Deposition: Positive
Boiling: Negative
Melting: Negative</span>
