Answer:
I think c biological processes
Answer:
here:
Explanation:
The changes in temperature caused by a reaction, combined with the values of the specific heat and the mass of the reacting system, makes it possible to determine the heat of reaction.
Heat energy can be measured by observing how the temperature of a known mass of water (or other substance) changes when heat is added or removed. This is basically how most heats of reaction are determined. The reaction is carried out in some insulated container, where the heat absorbed or evolved by the reaction causes the temperature of the contents to change. This temperature change is measured and the amount of heat that caused the change is calculated by multiplying the temperature change by the heat capacity of the system.
The apparatus used to measure the temperature change for a reacting system is called a calorimeter (that is, a calorie meter). The science of using such a device and the data obtained with it is called calorimetry. The design of a calorimeter is not standard and different calorimeters are used for the amount of precision required. One very simple design used in many general chemistry labs is the styrofoam "coffee cup" calorimeter, which usually consists of two nested styrofoam cups.
When a reaction occurs at constant pressure inside a Styrofoam coffee-cup calorimeter, the enthalpy change involves heat, and little heat is lost to the lab (or gained from it). If the reaction evolves heat, for example, very nearly all of it stays inside the calorimeter, the amount of heat absorbed or evolved by the reaction is calculated.
Answer:
(a) 3:2; (b) 2:1
Explanation:
The Law of Multiple Proportions states that when two elements A and B combine to form two or more compounds, the masses of B that combine with a given mass of A are in the ratios of small whole numbers.
That is, if one compound has a ratio r₁ and the other has a ratio r₂, the ratio of the ratios r is in small whole numbers.
(a) Ammonia and hydrazine.
In ammonia, the mass ratio of H:N is r₁ = 0.2158/1
In hydrazine, the mass ratio of H:N is r₂ = 0.1439/1
The ratio of the ratios is:
(b) Nitrogen oxides
In nitrogen monoxide, the mass ratio of O:N is r₁ = 1.142/1
In dinitrogen monoxide, the mass ratio of O:N is r₂ = 0.571/1
The ratio of the ratios is:
Answer:
8.60 * 
atoms N2
Explanation:
We want to convert grams to moles and then moles to atoms.
First, we convert grams of nitrogen gas (which is N2) to moles. To do so, we need the molar mass of N2, which is just 14.01 * 2 = 28.02 g.
40 g N2 * 
= 1.43 mol N2
Now, we need to convert moles to atoms by using Avogadro's number, which is 
:
1.43 mol N2 * 
= 8.60 * atoms N2
Thus, the answer is 8.60 * atoms N2.
Fossil fuels about into Earth ice age time
