A chain reaction is a nuclear reaction that occurs when sufficient unstable nuclei are present so that when one splits (decays), its products hit other unstable nuclei, causing them to decay and initiating a chain reaction.
If this reaction goes uncontrolled, a massive explosion occurs. Such a reaction is the type that went uncontrolled when nuclear bombs were dropped over Hiroshima and Nagasaki in World War II. A chain reaction is much like dominoes all in a row; when one goes down, they all go down in order. The only way to block the chain reaction is to pull out a domino or to block the fall so the "chain" is broken.
The amount of fissionable material needed to accomplish a spontaneous chain reaction is called the critical mass. The critical mass for U-235 is about 1 kg. This explosive fission process takes place quickly, and an incredible amount of energy is released when it occurs.
So it would be C.
the answer for this is c
sedimentary rocks
igneous rocks
metamorphic rocks
all of the above
Question 18 (Multiple Choice Worth 1 points)
Thermal expansion is an example of
mechanical weathering
chemical weathering
erosion
molecular weathering
Question 19 (Multiple Choice Worth 1 points)
Erosion is the
movement of rock from one place to another
breakdown of rock due to physical means
breakdown of rock due to chemical means
compaction and cementation of small rock particles
Question 20 (Multiple Choice Worth 1 points)
Sediment being placed at a new location by erosion is known as
transportation
placement
deposition
installation
Question 21 (Multiple Choice Worth 1 points)
Which process describes large areas of land being converted into cities?
Deforestation
Desertification
Suburban sprawl
Urbanization
Question 22 (Multiple Choice Worth 1 points)
A rock showing signs of intense heat and pressure is found at the top of a mountain. This is most likely what type of rock?
Igneous
Metamorphic
Sedimentary
None of the above
Question 23 (Multiple Choice Worth 1 points)
Which of the following is a positive effect of building a bridge?
Destruction of wildlife habitat
Dredging
Pollution from construction
Ease of traffic movement
Question 24 (Multiple Choice Worth 1 points)
The most accurate way to date a rock is by using
relative dating
absolute dating
the law of superposition
estimates based on where it is found
Question 25 (Multiple Choice Worth 1 points)
A mineral that breaks in a rough jagged way is said to exhibit
cleavage
fracture
spiral
shatter
Question 26 (Multiple Choice Worth 1 points)
One positive effect of deforestation is
decreased natural beauty
increased farm land producing food for people
increased erosion
decreased animal habitat
Answer:BaCl2 + Al2(SO4)3 -->BaSO4 + AlCl3.
Explanation:
solids?
Answer: group 1(alkali metal)
Explanation:
Answer:
the answer is the alkali metals
A They are able to find food easier.
B They have higher reproductive rates.
C They use energy more efficiently.
Answer: B They have higher reproductive rates.
Asexual reproduction is a mode of reproduction, which takes place in simple organisms. This mode of reproduction does not require the formation of gametes by the living organisms. The offsprings produced are usually larger in number as compared to those produced in the sexual mode of reproduction. The offsprings are genetically identical to the parent organisms.
Although, the life span of the asexually reproducing organisms is low, and the organisms produced are typically shorter than the sexually reproducing organisms. But, they have higher reproductive rates than sexually reproducing organisms. This because of the fact that these organisms are simple. They do not require to form or develop sex cells like sexually reproducing organisms. They just require favorable environment conditions to develop a new organism. For example, budding in yeast, the bud develops as an outgrowth on mother yest cell, which detaches in maturity and germinate to form new yeast organism.