Answer:2 hours
This range of temperatures is often called the "Danger Zone." Never leave food out of refrigeration over 2 hours. If the temperature is above 90 °F, food should not be left out more than 1 hour. Keep hot food hot—at or above 140 °F.
Explanation:
during a chemical reaction when the products of that reaction require less potential energy describe what happens to the surroundings?
why can't you balance CaC2 + H2O > Ca(OH)2 + CH4?
Answer:
Balance The Chemical Equation Cac2 H2o Ca Oh 2 C2h2 Balance the chemical equation CaC 2 + H 2 O → Ca (OH) 2 + C 2 H 2 Calcium carbide react with water to produce calcium hydroxide and acetylene.
Explanation:
CaC2 + H2O > Ca(OH)2 + CH4
Ca + 2 H2O → Ca(OH)2 + H2 - Balanced equation
What is balance equation with example?A balanced chemical equation occurs when the number of the atoms involved in the reactants side is equal to the number of atoms in the products side. In this chemical reaction, nitrogen (N2) reacts with hydrogen (H) to produce ammonia (NH3). The reactants are nitrogen and hydrogen, and the product is ammonia
What is the balance chemical formula?Balanced chemical equation - A chemical equation in which the number of each type of atom is equal on the two sides of the equation. Subscripts - Part of the chemical formulas of the reactants and products that indicate the number of atoms of the preceding element.
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what is the technique for measuring the heat change for a reaction called?
Answer: calorimetry
Explanation: calorimetry: the measure of the amount of heat involved in a chemical or physical process.
If a substance has a mass of 0.00235 grams and you need the mass in milligrams, will the number appear to become smaller or larger
A block of aluminum weighs 50.0g it's density is 2.70 g/cm3 what is the volume of a block
Answer:
18.51g/cm³
Explanation:
Mass=50.0g
Density =2.7g/cm³
Volume =Mass/Density
Volume =50/2.7
Volume =18.51g/cm³
What causes the liquid in a thermometer to rise?
Answer:
The level of colored liquid rises when the thermometer is placed in hot water. Heat causes the molecules of the liquid to get farther apart. The molecules of the liquid break down into atoms and take up more space.
Explanation:
I have a question does Neptune have a atmosphere?
Answer:
Neptune has a dynamic atmosphere with a shroud of cold clouds. The average cloud temperature ranges from about -240 degrees to -330 degrees F.
Helpp meeee the picture is above.
Answer:
a) 2.7 g cm³
b) 10.2 g
Explanation:
a) Density = Mass/Volume
= 21.6/8.00
= 2.7 g cm³
b) Mass = Volume × Density
= 2.55 × 4.0
= 10.2 g
Which measurement of a star depends on the distance of the star from earth?
A. luminosity
B. apparent magnitude
C. absolute magnitude
D. surface temperature
Answer:
[tex](b) \: apparent \: magnitude \\ \\ [/tex]
Explanation:
Astronomers define star brightness in terms of apparent magnitude — how bright the star appears from Earth — and absolute magnitude — how bright the star appears at a standard distance of 32.6 light-years, or 10 parsecs.
MARK ME AS A BRAINLIST PLZ
The measurement of a star depends on the distance of the star from earth
is Apparent magnitude.
What is Apparent Magnitude?
The apparent magnitude of a star is how bright the star appears in the sky
from the earth. The apparent magnitude of a star depends on two main
factors known as:
Absolute brightnessDistance.These factors help to accurately determine the brightness of stars in the
solar system.
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significant figures and scientific notation practice.
Answer:
11: 4
12: 3
13: 1
17: 3.000060
18: 5.0 x 10^2
19: 5.0 x 10^6
Explanation:
11: digits between 1&9 are always signifigant even if there are zeros between them
13: Zeros after the decimal do not count unless they represent an exact measurement
18: The decimal point moves forward 2 units so 10^2
what is the only process that removes carbon from the atmosphere
Answer:
Photosynthesis process
Explanation:
Photosynthesis removes carbon dioxide naturally — and trees are especially good at storing carbon removed from the atmosphere by photosynthesis.
Use the information about igneous rocks A-D to classify each one as intrusive or extrusive and basaltic or granitic. Fill in the
chart with A, B, C, or D.
Rock A-dark-colored large grains
Rock B-large crystals, high percentage of silica
Rock C-fine-grained texture, light-colored
Rock D—from Hawaiian volcano area, no visible crystals
Extrusive
Intrusive
1.
2.
Basaltic
Granitic
3.
4.
Answer:
1. D 2.. A 3. C 4. B
Explanation:
just took the quiz
We can classify each rock as intrusive or extrusive and basaltic or granitic as follows; Rock A - Extrusive, Basaltic, Rock B - Intrusive, Granitic, Rock C - Extrusive, Basaltic, and Rock D - Extrusive, Basaltic.
Rock A - Extrusive, Basaltic
Rock A is described as having dark-colored large grains, which indicates a fine-grained texture, typical of extrusive rocks. The presence of dark-colored large grains suggests a basaltic composition.
Rock B - Intrusive, Granitic
Rock B is described as having large crystals and a high percentage of silica, which suggests a coarse-grained texture, typical of intrusive rocks. The high silica content and large crystals indicate a granitic composition.
Rock C - Extrusive, Basaltic
Rock C is described as having a fine-grained texture and being light-colored, which are characteristic features of extrusive rocks. The fine-grained texture suggests a rapid cooling, typical of extrusive rocks, and the light color is indicative of a basaltic composition.
Rock D - Extrusive, Basaltic
Rock D is described as being from the Hawaiian volcano area and having no visible crystals. This indicates a glassy texture, typical of rapidly cooled extrusive rocks. The origin from a volcanic area and glassy texture suggest a basaltic composition.
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If there is H2O and O2 what it's going to be
Answer:
o232
Explanation:
A school bus travels 270 km in 6 hr. What is its average speed for the trip in km/hr?
Answer:
45km/hr
Explanation:
270/6=45
Read the following paragraph from the section "Dreaming Of A World Deep Below."
The interior of our planet has long held a fascination for philosophers and storytellers. Some have speculated that another inhabited world lies beneath our own. In 1864, Jules Verne’s novel "Journey to the Center of the Earth" described the fictional adventures of explorers traveling under our planet’s surface. It was a best-seller. People wondered if the world Verne described below our own could be real.
Why does the author include this paragraph in the article?
Question 9 options:
to show how much scientific progress regarding the Earth's core was made during Lehmann's lifetime
to explain a number of popular theories concerning the composition of the Earth's core
to demonstrate how Lehmann's discovery confirmed what Jules Verne already knew about the Earth's core
to describe the attitudes Lehmann needed to overcome in order to introduce her work to the scientific community
Answer:
B
Explanation:
The interior planet has fascinated a lot of people so a lot of theories have been made about what's in there.
The reason author include this paragraph in the article is to explain a number of popular theories concerning the composition of the Earth's core. Thus, option B is correct.
What is acronym?
Acronym has been defined as the short form of long words such as very important person and the acronym of very important person has been VIP. The word acronym has been used to denote the short term of the word in which two or more than two words combined together to form new short word.
Acronym always starts with capital latter and the first word's letter is always capital. Capitalization has been the most important part of the writing as it has the rule of writing that the first latter of the word that starts a sentence must be capital or starts with capital latter.
The sentence has a group of sensible or meaningful word that combines together to form a complete and senseful sentence. The sentence has of several type such as positive sentence, negative sentence, exclamatory sentence as well as introgative sentence.
Therefore, The reason author include this paragraph in the article is to explain a number of popular theories concerning the composition of the Earth's core. Thus, option B is correct.
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18. What is the volume of these gases at STP?
a. 3.20 x 10 mol CO2
b. 3.70 mol NH2
C. 0.960 mol CH4
Answer:
B 3.70 mol NH2
Explanation:
Answer:
A. 0.0717 L
B. 82.9 L
C. 21.5 L
the _____ of an object is where the object is in relation to another object or points of reference. A motion B force C gravity D position
d position
position is the reference for the points of the object
5. _______ is the combining capacity of atom with other atoms to form a molecule or a compound .
Answer:
valancy
Explanation:
any push or pull is called
Answer:
A Force.
Explanation:
A force is a push or pull upon an object resulting from the object's interaction with another object. ... Forces only exist as a result of an interaction.
how many water molecules self ionize in one liter of water
Answer:
yes
Explanation:
because I think it is correct fo u
Is this true or false for this question?!
Answer:
True, Electrons are way smaller then protons
Explanation:
who wanna ft on snap? I'm a guy btw
hahahaha your a guy
Explanation:
brainliest me please
Someone pls help me I will make you brain
Answer:
less methane
Explanation:
methane is increasing because of global warming
is the formation of the grand canyon a physical or chemical change
Answer:
Its a physical change I believe
Explanation:
Your teacher has just asked you to measure out 1.24 x 1023 molecules of sodium chloride, Sodium chloride has a chemical formula of Naci. Using a Periodic Table,
determine how many grams of sodium chloride you should measure out.
A 12.08
2.12 x 1028
284 g
D 72.5 x 1021 g
Answer:
A)
Explanation:
An ion has 56 protons, 54 electrons, and 81 neutrons. What is its atomic #?
Answer:
110.91982
The element is probably Barium
The atomic number of an atom is equal to the number of protons it has. In this case, the ion has 56 protons. Therefore, the atomic number of the ion is 56.
The atomic number or nuclear charge number (symbol Z) of a chemical element is the charge number of an atomic nucleus. For ordinary nuclei composed of protons and neutrons, this is equal to the proton number (np) or the number of protons found in the nucleus of every atom of that element. The atomic number can be used to uniquely identify ordinary chemical elements. In an ordinary uncharged atom, the atomic number is also equal to the number of electrons.
For an ordinary atom which contains protons, neutrons and electrons, the sum of the atomic number Z and the neutron number N gives the atom's atomic mass number A. As there are 56 protons thus the atomic number of the ion is 56.
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Select the reactants of photosynthesis
what is the maximum theoretical number of water molecules with which, in theory, one urea molecule can hydrogen bond?
Answer:
The maximum number of molecules that one water molecule can hold through hydrogen bonding is 4 because the two hydrogen atoms of water can form two hydrogen bonds and the two lone pairs on oxygen can also form two hydrogen bonds. hope it helps
PLEASE HELPP!
True or False: Hydrogen is an alkali metal.
Answer: falso
Explanation:
What is the most common ion charge of chromium? Where on the periodic table?
Answer:
i
Explanation:
The most common oxidation states of chromium are +6, +3, and +2. On the metal area of the periodic table.
Explanation: