Answer:
The geologist time scale was formed when scientists studied rock layers and index fossils worldwide. With this information, they placed Earth's rocks in order by relative age. Later, radioactive dating helped determine the exact age of the divisons in the geologic time scale.
This scale is organized by the 4.6 billion years of earth's history into sections based on important changes seen in the geologic record. The largest intervals are called eons, with each eon containing many millions of years.
In precambarian time the processes that affect Earth's surface have lessened the erosion on the surface. Earth was being hit by meteorites every second. Now there is water erosion and there wasn't back then. The surface changes have lessened over time.
Answer:
Exothermic.
Explanation:
Exothermic is when he leaves the system. A way to remember is the "ex" which is a prefix/root/suffix or something that pretty much means leaving, I think. For example how it's in "Exodus" and "Exit", I think.
Endothermic is when it goes into the system. Similar to "ex" but with inside, I think. For example how it's in "Endoskeleton", I suppose.
Answer:
The mass of tin is 164 grams
Explanation:
Step 1: Data given
Specific heat heat of tin = 0.222 J/g°C
The initial temeprature of tin = 80.0 °C
Mass of water = 100.0 grams
The specific heat of water = 4.184 J/g°C
Initial temperature = 30.0 °C
The final temperature = 34.0 °C
Step 2: Calculate the mass of tin
Heat lost = heat gained
Qlost = -Qgained
Qtin = -Qwater
Q = m*c*ΔT
m(tin)*c(tin)*ΔT(tin) = -m(water)*c(water)*ΔT(water)
⇒with m(tin) = the mass of tin = TO BE DETERMINED
⇒with c(tin) = the specific heat of tin = 0.222J/g°C
⇒with ΔT(tin) = the change of temperature of tin = T2 - T1 = 34.0°C - 80.0°C = -46.0°C
⇒with m(water) = the mass of water = 100.0 grams
⇒with c(water) = the specific heat of water = 4.184 J/g°C
⇒with ΔT(water) = the change of temperature of water = T2 - T1 = 34.0° C - 30.0 °C = 4.0 °C
m(tin) * 0.222 J/g°C * -46.0 °C = -100.0g* 4.184 J/g°C * 4.0 °C
m(tin) = 163.9 grams ≈ 164 grams
The mass of tin is 164 grams
Br2 is the correct answer
Hey there!
The correct answer to your question is option A.
Sugar dissolving in warm water is an example of a physical change.
This is because sugar dissolving in the water does not create a substance or material. All of the other options are examples of chemical changes, because they eventually become a substance/material.
Hope this helps you.
Have a great day!
