Are the nuclei of all atoms
a) Positive
b) Negative
c) Neutral
2 points
A student saw the Moon rise at 6:20 a.m. on Monday. If he wants to see
the Moon rise again on Tuesday, vhat time should he look in the sky?(Mark
the one best answer.)
About 6:20 am
About 6:20pm
About 5:30 am
About 7:10am
A student is investigating potential and kinetic energy by stretching a spring across a table. When the student lets go
The spring recoils.
Answer: When the spring is recoiling
Explanation:
Answer:
When the spring is recoiling
Explanation:
Provide one example of how life on Earth would not be possible without water based on its characteristics.
Answer: ice is less dense than liquid water. If ice was more dense, Earth would freeze.
Explanation: There are many reasons why life on Earth depends on the characteristics of water. One could discuss hydrogen bonds and its role as a solvent, but the unusual property of water is is the change in density with change in temperature. Water is densest at 4 degC, which is why ice floats - it is less dense than cold water (it melts quickly in warm water, so density isn’t impotant at higher temperatures). Most liquids are less dense than the solid, frozen form. If this was the case with water, any ice that formed would sink, and sease would freeze from the bottom up. Furthermore, the lowest layers would be insulated and would not all melt in summer. Thus over time, the seas would become a thin layer of liquid water at best, over solid ice. Life could not develop without liquid seas. In addition, ice is reflective, reducing the amount of sunlight absorbed, further reducing temperatures. Without ocean circulation, polar areas would be even colder, and there would be no rain.
Which two mantle hot spots are located at mid-ocean
ridges?
Answer:
This region of thick, hot crust and mantle extends 1,300 kilometers north and south of the Iceland hotspot and some 1,000 kilometers north and south of the Azores hotspot. Together, the two hotspots appear to be feeding a huge supply of magma to nearly the entire northern segment of the Mid-Atlantic Ridge.
Explanation:
please give me a heart
Answer:
Easter island
Which way does heat transfer from warm objects to cool objects, or from cool objects to warm objects?
A symbiotic relationship in which both organisms benefit
A. parasitism
B. mutualism
C. commensalism
Answer: B
Mutualism.
Explanation:
You have 11 blue cars, 7 red cars and 4 green cars
What percent of cars are green?
Answer to 1 Decimal Place (Check your rounding)
Emitted energy is reported in megaelectron volts (MeV), where one MeV is equal to one million electron volts. How much energy is emitted in this reaction?
Answer:
1.44
Explanation:
Science happened in my brain
Which of the following is NOT a major area of scientific study?
Answer:
Hate 2 break it 2 u foo but there's no option for me 2 choose....
why do pengiuns have beards
Answer:
no they do not
Explanation:
Answer:
It's just...Hair grown there...i guess it just grows as a male humans would
Explanation:
hope this helps.
If an object has a density of 25 g/cm and a mass of 100 grams, what is its volume? O 40 cm3 0.25 cm 4 cm3 125 cm3
4 cm³
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightEquality Properties
Multiplication Property of Equality Division Property of Equality Addition Property of Equality Subtract Property of EqualityChemistry
Gas Laws
Density = Mass over Volume
D = m/V Explanation:Step 1: Define
D = 25 g/cm³
m = 100 g
Step 2: Solve for V
Substitute variables [D]: [tex]\displaystyle 25 \ g/cm^3 = \frac{100 \ g}{V}[/tex]Multiply V on both sides: [tex]\displaystyle V(25 g/cm^3) = 100 \ g[/tex]Isolate V: [tex]\displaystyle V = 4 \ cm^3[/tex]
How many hydrogen atoms are in 5 molecules of isopropyl alcohol, C3H7O ?
Answer:
The answer is "35 atoms".
Explanation:
The Formula for isopropyl alcohol is: [tex]C_3H_8O[/tex]
In 1 molecule of [tex]C_3H_8O[/tex] = 8 atoms of hydrogen
In 4 molecule of = atoms of hydrogen
According to the given formula [tex]C_3H_7O[/tex]
In 5 molecule of [tex]C_3H_7O[/tex] [tex]= 5 \times 7 = 35[/tex] atoms of hydrogen.
how does mixture relate to your life
PLEAEEEE QUICKKKK AND FASTTT
Which of the following best describes how water evaporates? *
3 points
A. Water molecules that move with higher energy evaporate first
B. Water molecules that are cooled evaporate
C. None of the above
What happens at all convergent plate boundaries?
Explanation:
At convergent plate boundaries two plates are moving towards one another and different scenarios are in play.
Most importantly, at these margins the crust is being destroyed.
At continental - continental crust margin, there is an uplift because the density of the two crust is similar and lesser than that of the mantle below. At continental - oceanic crust margin, subduction zones are found where the denser oceanic crust sinks beneath into the mantle. This is also the case with ocean - ocean convergence zone.Some of the features found at this margin include, oceanic trenches, accretionary wedges, volcanic islands, earthquakes
d. Calculate the initial reaction rate that would be seen in a solution in which [BF3] is 5.0 x10 -1M and [NH3] is 2.0 x10 -2 M
Answer:
[tex]r=0.0341\frac{M}{s}[/tex]
Explanation:
Hello!
In this case, considering the given table, we are able to represent the symbolic rate law as shown below:
[tex]r=k[BF_3]^m[NH_3]^n[/tex]
Thus, by using the following steps, we can find both m (BF3 order of reaction) and n (BF3 order of reaction):
- Experiment 1 and 2 for the calculation of n:
[tex]\frac{r_1}{r_2}=\frac{k[BF_3]_1^m[NH_3]_1^n}{k[BF_3]_2^m[NH_3]_2^n}[/tex]
So we plug in to obtain:
[tex]\frac{0.2130}{0.1065}=\frac{k*0.250^m*0.250^n}{k*0.250^m*0.125^n}\\\\2=\frac{0.250^n}{0.125^n}\\\\2=2^n\\\\log(2)=n*log(2)\\\\n=1[/tex]
So the order of reaction with respect to NH3 is 1.
- Experiment 3 and 4 for the calculation of m
[tex]\frac{r_3}{r_4}=\frac{k[BF_3]_3^m[NH_3]_3^n}{k[BF_3]_4^m[NH_3]_4^n}[/tex]
So we plug in to obtain:
[tex]\frac{0.0682}{0.1193}=\frac{k*0.200^m*0.100^n}{k*0.350^m*0.100^n}\\\\0.57=0.57^m\\\\log(0.57)=m*log(0.57)\\\\m=1[/tex]
So the order of reaction with respect to BF3 is also 1.
Now, we can compute the rate constant by solving for it on any of the experiments there, say experiment 1:
[tex]k=\frac{r_1}{[BF_3][NH_3]} =\frac{0.2130M/s}{0.250M*0.250M}\\\\k=3.41M^{-1}s^{-1}[/tex]
Thus, the initial reaction rate for the 0.50M BF3 and 0.020M NH3 is:
[tex]r=3.41M^{-1}s^{-1}*0.50M*0.020M\\\\r=0.0341\frac{M}{s}[/tex]
Best regards!
50 POINTS How many liters of O2 gas are in 4.21 moles?
and How many liters of PH3 gas are in 14.71 moles?
Explanation:
I mol of water = 22.4 lts of O2
thus, 4.21 moles of water = 4.21× 22.4= 94.304 lts.
What reactive species is produced in the initiation step of the free radical chlorination of 2,2-dimethylpropane
Answer:
See explanation
Explanation:
An initiation step is the first step in a free radical mechanism. In this step, free radicals are generated from a stable compound. The initiation step tends to increase the concentration of radicals present in the system. It leads to a net increase in the number of free radicals in the system.
For the chlorination of 2,2-dimethylpropane, the initiation step is;
Cl2 + hv --------->2Cl.
Note that hv is used to represent light
what's the pH of a solution composed of 0.2 moles of NH3 and 0.15 moles of nh4cl
Answer:
[tex]pH=4.63[/tex]
Explanation:
Hello!
In this case, since the ionization of ammonia, which is a weak base, is written as:
[tex]NH_3+H_2O\rightleftharpoons NH_4^++OH^-[/tex]
We can see that the ammonium ion is the conjugate acid whereas the hydroxide ions the conjugate base; that is why we use the Henderson-Hasselbach equation to compute the pH, given the pKb of ammonia 4.75:
[tex]pH=pKb+log(\frac{[conj\ acid]}{[base]} )[/tex]
In such a way, for the given moles of ammonia, base, and those of ammonium chloride, conjugate acid form, we obtain:
[tex]pH=4.75+log(\frac{0.15}{0.2} )\\\\pH=4.63[/tex]
Best regards!
Please help me thanks so much....I’ll mark you?!?!:))))
Answer:
chemical
Explanation:
HEY THIS ANSWER CORRECT ?
Answer:
I don't think that answer is right. I got 543.04 grams.
Explanation:
I think the question is asking for grams in the samlpe instead of the moles in the sample because it already gives you the amount of moles.
How many grams are in 4.7 moles of Na2O?
290 g Na₂O
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Reading a Periodic TableUsing Dimensional AnalysisExplanation:Step 1: Define
4.7 mol Na₂O
Step 2: Identify Conversions
Molar Mass of Na - 22.99 g/mol
Molar Mass of O - 16.00 g/mol
Molar Mass of Na₂O - 2(22.99) + 16.00 = 61.98 g/mol
Step 3: Convert
Set up: [tex]\displaystyle 4.7 \ mol \ Na_2O(\frac{61.98 \ g \ Na_2O}{1 \ mol \ Na_2O})[/tex]Multiply: [tex]\displaystyle 291.306 \ g \ Na_2O[/tex]Step 4: Check
Follow sig fig rules and round. We are given 2 sig figs.
291.306 g Na₂O ≈ 290 g Na₂O
The density of benzene is 0.879g/mL. The volume (with 1 decimal) of 131.9g sample of benzene is how many mL?
Answer:
150.1 mL
Explanation:
Step 1: Given data
Density of benzene (ρ): 0.879 g/mLMass of the sample of benzene (m): 131.9 gVolume of the sample of benzene (V): ?Step 2: Calculate the volume of the sample of benzene
Density is an intrinsic property. It is equal to the quotient between the mass and the volume of the sample of benzene.
ρ = m/V
V = m/ρ
V = 131.9 g/(0.879 g/mL)
V = 150.1 mL
Why is it important to have control???
Answer:
A control is important for an experiment because it allows the experiment to minimize the changes in all other variables except the one being tested.
Explanation:
do u mean that kind of control
11)
B.
A.
D.
Which position represents spring in the southern hemisphere?
A)
А
B)
B
C)
С
D)
D
Answer:
Cccccccccccccccccccccccccccccccccccccccccccc
PLEASE HELP PLEASEEESSSS
Answer:
The answer is C or 3 which ever but it that one
Explanation:
A student read an article about natural resources and listed some resources in the
chart shown. Which answer choice best classifies the natural resources in the chart?
Natural Resources
Coat
Air
Tree
Petroleum
Wheat
Natural
gas
Sheep
Lake
Fish
Answer:
Explanation:
Airs and trees
Moving glaciers can cause erosion ?
True or false
Plz explain
Answer:
true
Explanation:
plucking and abrasion
abrasion is when a glacier scrapes rocks below and plucking is when sediments are picked up by a glacier
Write a balanced equation describing the reduction of H2SeO4 by SO2 to produce selenium. (Use the lowest possible coefficients. Include states-of-matter under SATP conditions in your answer.)
Answer:
[tex]\mathbf{H_2SeO_{4(aq)} + 3SO_{2(aq)} + 2H_2O_{(l) } \to Se_{(s)} + 3H_2SO_{4(aq)} }[/tex]
Explanation:
We are to write a balanced equation from the information given above by including the states of their matter according to SATP conditions;
[tex]\mathbf{H_2SeO_{4(aq)} + 3SO_{2(aq)} + 2H_2O_{(l) } \to Se_{(s)} + 3H_2SO_{4(aq)} }[/tex]
From above;
The oxidizing agent is [tex]\mathbf{H_2SeO_{4(aq)} }[/tex]
The reducing agent is [tex]\mathbf{SO_{2(aq)} }[/tex]