Answer:
The correct answer is 25 mL graduated cylinder (it should be used in all the cases)
Explanation:
In order to measure 25.00 ml sample of a solution it should be used a 25 mL graduated cylinder, as it is previously and properly calibrated. The other laboratory glassware, beaker and erlenmeyer, have graduations which are approximate, so they are used when exact volumes are not needed.
ii) graduated cylinder has the least uncertainly. It is more accurate than a beaker or erlenmeyer (to within 1%)
iii) A 25 mL graduated cylinder should be used because it is the most accurate lab glassware (between those were mentioned: beaker, erlenmeyer).
Answer:
All of the above are true
Explanation:
a) The emission spectrum of a particular element is always the same and can be used to identify the element: It's true since the emission spectrum for each element is unique. It has the same bright lines at the same wavelength. This feature is used to identify elements. For example, the study of the emission spectra of light arriving from stars allow us to identify the elements presents in the star because the light contains the emission spectra of those elements.
b)The uncertainty principle states that we can never know both the exact location and speed of an electron: It is true since the velocity of an electron is related to its wave nature, while its position is related to its particle nature and we cannot simultaneously measure electron's position and velocity with precision.
c) An orbital is the volume in which we are most likely to find an electron: An orbital is a probability distribution map that is used to decribe the likely position of an electron in an atom.
Answer:
C. 3
Explanation:
12.0 - 3 significant figures 1,2 and 0, because 0 is after decimal point.
Answer: Natural gas has a faster rate because, being a carbon resource, it quickly replenishes as part of the carbon cycle.
Explanation:
Natural gas is a natural gas which consists of mixtures of hydrocarbons. It is primarily composed of methane, alkanes, small percentage of nitrogen, hydrogen sulfide, helium and carbon dioxide.
Being a carbon source it can be replenished easily due to decomposition of organic matter generated after the decomposition of dead animal and plant matter.
The geothermal energy can be define as the energy obtained from the hot springs it includes the water that includes the thermal energy generate through heat present in the geosphere.
Although the geothermal energy is the renewable source of energy but the time and period of it's generation remains unknown from the hot spring. Therefore, the rate of renewal of energy of natural gas is faster than the geothermal energy.
When the materials are heated they undergo a chemical change. The reaction is non reversible. The sugar, flour and eggs can no longer be separated. The properties of the materials have changed so it is a chemical change.
