Units of the SI System
There are seven base units in the SI system:
the kilogram (kg), for mass
the second (s), for time
the kelvin (K), for temperature
the ampere (A), for electric current
the mole (mol), for the amount of a substance
the candela (cd), for luminous intensity
the meter (m), for distance
Why does our body need to use both mechanical and chemical digestion when we are breaking down our food?
Answer:
Chemical digestion is a vital part of the digestive process. Without it, your body wouldn't be able to absorb nutrients from the foods you eat, also chemical digestion uses enzymes to break down food
mechanical digestion involves physical movements, such as chewing and muscle contractions,
Explanation:
FIRST CORRECT ANSWER GETS 10 POINTS!!!!
Which explains how the nervous system is typically involved in keeping the body in homeostasis?
It processes the environment and sends out signals.
It controls movement and provides structure.
It physically breaks down and absorbs food.
It puts oxygen in the blood, which is essential for life.
Answer:
Explanation:
It processes the environment and sends out signals.
A self-aldol or crossed aldol reaction REQUIRES a(n) ___________________. Group of answer choices strong acid only a very, very strong base, such as LDA (lithium diisopropyl amide), NaOH or LiOH won't work acid catalyst a strong base such as LiOH or NaOH
Answer:
[tex]\mathbf{a \ strong \ base \ such \ as\ LiOH \ or \ NaOH.}[/tex]
Explanation:
In the condensation reactions of carbonyl compounds, it is essential to establish the order of events in advance to minimize or suppress the possibilities of self-condensation and the occurrence of cross-condensation, which unfortunately are an obvious threat in these reactions.
Self-condensation:
Any carbonyl compound that has one or more alpha hydrogens, on the carbons adjacent to the carbonyl group, runs the risk of undergoing a self-condensation reaction if the corresponding rigor is not carried out.
Cross-condensation:
Ideally, in the condensation reactions of carbonyl compounds, one of the reacting molecules should quickly enolise, while the other preferably should not have Hα, to ensure that no other by-products are formed.
[tex]\text{To achieve this process;}[/tex] [tex]\text{A self-aldol or crossed aldol requires a strong base such as LiOH or NaOH.}[/tex]
A 1.250-g sample of benzoic acid, C7H6O2, was placed in a combustion bomb. The bomb was filled with an excess of oxygen at high pressure, sealed, and immersed in a pail of water which served as a calorimeter. The heat capacity of the entire apparatus (bomb, pail, thermometer, and water) was found to be 10.134 kJ/K. The oxidation of the benzoic acid was triggered by passing an electric spark through the sample. After complete combustion, the thermometer immersed in the water registered a temperature 3.256 K greater than before the combustion. What is DEcombustion per mole of benzoic acid burned
Answer:
3224 kJ/mol
Explanation:
The combustion of benzoic acid occurs as follows:
C₇H₆O₂ + 13/2O₂ → 7CO₂ + 3H₂O + dE
The change in temperature in the reaction is the change due the energy released, that is:
3.256K * (10.134kJ / K) = 33.00kJ are released when 1.250g reacts
To find the heat released per mole we have to find the moles of benzoic acid:
Moles benzoic acid -Molar mass: 122.12g/mol-:
1.250g * (1mol / 122.12g) = 0.0102 moles
The dE combustion per mole of benzoic acid is:
33.00kJ / 0.0102moles =
3224 kJ/mol
Newton's second law states that force is equal to
mass times weight
mass times acceleration
weight divided by mass
weight times acceleration
salt in soap make the soap stronger
Answer:
yes correct salt hardens soap
What is the name of the anion in sodium carbonate?
Answer: Sodium salt
Explanation: sorry if this is wrong
Calculate the precise Molar Mass of NH3 and calculate the moles in 50.0
grams.
Answer: Molar mass of [tex]NH_3[/tex] is 17.00 g and moles in 50.0 grams is 2.94.
Explanation:
Molar mass is defined as the mass in grams of 1 mole of a substance.
S.I Unit of Molar mass is gram per mole and it is represented as g/mol.
Atomic Mass of Nitrogen (N) = 14.00 g
Atomic Mass of Hydrogen (H) = 1.00 g
Molar mass of [tex]NH_3[/tex] = 1(14.00)+3(1.00) g = 17.00 g
According to avogadro's law, 1 mole of every substance contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles and weigh equal to its molecular mass.
To calculate the moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}[/tex]
[tex]\text{Number of moles of }NH_3==\frac{50.0g}{17.00g/mol}=2.94moles[/tex]
There are clouds forming over Florida. The temperatures in the clouds and in the air are above freezing. Which form of precipitation do you expect Florida to get and why?
Answer:
Rain
Explanation:
Clouds are formed from water vapor, which turns into ice when the temperature is below freezing, and falls as liquid rain water when temperatures are above freezing. Since the temperatures in the clouds and in the air are above freezing, rain will fall in Florida.
Answer:
Rain
Explanation:
What mass of lithium phosphate would you mass to make 2.5 liter of 1.06 M lithium
phosphate solution?
Answer:
Approximately [tex]3.06 \times 10^{2}\; \rm g[/tex] (approximately [tex]306\; \rm g[/tex].)
Explanation:
Calculate the quantity [tex]n[/tex] of lithium phosphate in [tex]V = 2.5\; \rm L[/tex] of this[tex]c = 1.06\; \rm M = 1.06\; \rm mol \cdot L^{-1}[/tex] lithium phosphate solution.
[tex]\begin{aligned}n &= c \cdot V\\ &= 2.5\; \rm L \times 1.06\; mol \cdot L^{-1}\\ &= 2.65\; \rm mol\end{aligned}[/tex].
Empirical formula of lithium phosphate: [tex]\rm Li_3PO_4[/tex].
Look up the relative atomic mass of [tex]\rm Li[/tex], [tex]\rm P[/tex],and [tex]\rm O[/tex] on a modern periodic table:
[tex]\rm Li[/tex]: [tex]6.94[/tex].[tex]\rm P[/tex]: [tex]30.974[/tex].[tex]\rm O[/tex]: [tex]15.999[/tex].Calculate the formula mass of [tex]\rm Li_3PO_4[/tex]:
[tex]M(\rm Li_3PO_4) = 3 \times 6.94 + 30.974 + 4 \times 15.999 = 115.79\; \rm g \cdot mol^{-1}[/tex].
Calculate the mass of that [tex]n = 2.65\; \rm mol[/tex] of [tex]\rm Li_3PO_4[/tex] formula units:
[tex]\begin{aligned}m &= n \cdot M \\ &= 2.65\; \rm mol \times 115.79\; \rm g\cdot mol^{-1} \\ &\approx 3.06 \times 10^{2}\; \rm g \end{aligned}[/tex].
this organ has 2 parts, the cervix, which is the lower part that opens into the vagina, and the main body, called the corpus.
Answer:
The correct answer is - the uterus.
Explanation:
The uterus or the womb is an organ that appears to be pear-shaped and it is hollow from inside where the fetus is developed and it is also called the birth canal. The uterus has two parts one is the cervix and the other is the corpus.
The cervix makes the lower part of the uterus and opens up into the vagina the external reproductive organ of the females. The corpus is the part that makes the main body of the uterus. The uterus is present between the bladder and rectum where the egg fertilized and implanted itself.
Calculate the value of Kp at 227°C for the equilibrium: 3 A(g) ⇌ B(g) + D(g) Kc = 5.15
a. 7.52
b. 0.125
c. 96.0
d. 0.0653
e. 276
help plz ill give extra points
Answer: i think its d sorry if im wrong
Explanation:
Help pleaseeeeeee
Using your knowledge of alpha beta and Gamma decay and your periodic table practice using your ideas by completing the following equations
Answer:
20. ²⁴¹₉₅Am —> ²³⁷₉₃Np + ⁴₂He
21. ⁴²₁₉K —> ⁰₋₁β + ⁴²₂₀Ca
Explanation:
20. ²⁴¹₉₅Am —> __ + ⁴₂He
Let ⁿₘX be the unknown.
Thus, the equation becomes:
²⁴¹₉₅Am —> ⁿₘX + ⁴₂He
Next, we shall determine n, m and X. This can be obtained as follow:
241 = n + 4
Collect like terms
n = 241 – 4
n = 237
95 = m + 2
Collect like terms
m = 95 – 2
m = 93
Thus,
ⁿₘX => ²³⁷₉₃X => ²³⁷₉₃Np
Therefore, the complete equation is:
²⁴¹₉₅Am —> ²³⁷₉₃Np + ⁴₂He
21. __ —> ⁰₋₁β + ⁴²₂₀Ca
Let ʸₓZ be the unknown.
Thus, the equation becomes:
ʸₓZ —> ⁰₋₁β + ⁴²₂₀Ca
Next, we shall determine y, x and Z. This can be obtained as follow:
y = 0 + 42
y = 42
x = –1 + 20
x = 19
Thus,
ʸₓZ => ⁴²₁₉Z => ⁴²₁₉K
Therefore, the complete equation is:
⁴²₁₉K —> ⁰₋₁β + ⁴²₂₀Ca
answer with explanation and you’ll get brain list
Answer:
Option D.
Explanation:
6H₂ + P₄ → 4PH₃First we convert the given reactant masses into moles, using their respective molar masses:
4.00 g H₂ ÷ 2 g/mol = 2 mol H₂6.20 g P₄ ÷ 124 g/mol = 0.05 mol P₄0.05 moles of P₄ would react completely with (6*0.05) 0.3 moles of H₂. There are more H₂ moles than required, meaning H₂ is in excess and P₄ is the limiting reactant.
Now we calculate how many PH₃ moles could be formed, using the number of moles of the limiting reactant:
0.05 mol P₄ * [tex]\frac{4molPH_3}{1molP_4}[/tex] = 0.2 mol PH₃Finally we convert 0.2 mol PH₃ into grams, using its molar mass:
0.2 mol PH₃ * 34 g/mol = 6.8 gSo the correct answer is option D.
Ammonium chloride is produced in the thermochemical equation NH3 (g) + HCl (g) → NH4Cl (s) ΔH = –176 kJ.
How many moles of NH4Cl have been produced if the change in enthalpy is –528 kJ?
Answer:
3 moles of NH₄Cl
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
NH₃(g) + HCl(g) → NH₄Cl(s) ΔH = –176 kJ
From the balanced equation above,
1 mole of NH₄Cl where obtained when the change in enthalphy (ΔH) was –176 kJ.
Finally, we shall determine the number of mole of NH₄Cl produced when the change in enthalphy (ΔH) is –528 kJ. This can be obtained as follow:
From the balanced equation above,
1 mole of NH₄Cl where obtained when the change in enthalphy (ΔH) was –176 kJ.
Therefore, Xmol of NH₄Cl will be obtained when the change in enthalphy (ΔH) is –528 kJ i.e
Xmol of NH₄Cl = –528 / –176
Xmol of NH₄Cl = 3 moles
Thus, 3 moles of NH₄Cl where obtained from the reaction.
in the ideal gas law which variable represents the gas constant?
a: T
b: R
c: n
d: V
e: P
Explanation:
It is represented using the ideal gas equation , or PV = nRT, where P is the pressure in atmospheres, V is the volume in liters, n represents the quantity of particles in the container, T represents the temperature in Kelvin, and R is the ideal gas constant equal to 0.0821 liters atmospheres per moles Kelvin.
According to the Arrhenius concept, an acid is a substance that ________. According to the Arrhenius concept, an acid is a substance that ________. tastes bitter can accept a pair of electrons to form a coordinate covalent bond is capable of donating one or more H reacts with the solvent to form the cation formed by autoionization of that solvent causes an increase in the concentration of H in aqueous solutions
Answer: According to the Arrhenius concept, an acid is a substance that causes an increase in the concentration of H in aqueous solutions
Explanation:
According to the Arrhenius concept, an acid is a substance that ionizes in the water to give hydronium ion or hydrogen ion and a bases is a substance that ionizes in the water to give hydroxide ion .
[tex]HA(aq)\rightarrow H^+(aq)+A^-(aq)[/tex]
[tex]BOH(aq)\rightarrow B^+(aq)+OH^-(aq)[/tex]
According to lewis concept , an acid is a substance that accepts electrons and a base is a substance that can donate electrons.
K2S(s) + MgI2 (aq) -----> ?
Answer:
MgS + KI = K2S + MgI2
A(n) ____________ is a push or a pull.
newton
acceleration
force
momentum
what adaptation help protect a cactus against herbivores
Answer:
spines
Cacti have spines, which are also called needles or thorns. Spines are modified leaves or leaves that have changed. Spines do not dry out. Spines deter herbivores from consuming this plant.
Explanation:
hope this helps...
Answer: Tunneling underground to offer protection from predators and extreme temperatures.
Explanation: A behavioral adaptation aimed at attracting a mate. A physical adaptation that allows birds to catch prey. Modified leaves that protect a cactus from herbivores.
I NEED HELP PLS ;-; !!!!
Identify the number of electrons each of the following atoms needs to gain or lose to have a stable outer electron configuration.
a. sodium (Na)
b. strontium (Sr)
c. sulfur (S)
d. astatine (As)
If you were sitting near a gram of protactinium-234 and a gram of uranium-234, both solid materials, which would you consider more dangerous to you?
aswer: protactinium-234 is more dang erous than uranium
There can be emissions of radiations like gamma radiation. There can be emission of particles too like alpha particle. Therefore protactinium-234 is more dangerous than uranium-234.
What is nuclear decay?Nuclear decay is process in which the radioactive element releases particles or radiations. Alpha particles is ⁴₂He. Alpha particle is nothing but helium particle. Protactinium-234 and uranium-234 are radioactive element.
If we were sitting near a gram of protactinium-234 and a gram of uranium-234, both solid materials then protactinium-234 is more dangerous than uranium-234. The half-life of protactinium-234 is smaller than that of uranium-234. So, protactinium-234 is more active than uranium-234 and hence more harmful than uranium-234.
Therefore, protactinium-234 is more dangerous than uranium-234.
To know more about nuclear decay, here:
https://brainly.com/question/21114779
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If a candy bar contains 345 Calories, how many calories is this?
Answer: 345,000 calories
Explanation:
Calories in food such as candy bars refer to the amount of energy that the food has. Calories are also called Kilocalories because they are the equivalent of 1,000 calories.
If the candy bar contained 345 calories therefore, and 1 Calorie is 1,000 calories, the calories in the candy bar are:
= 345 * 1,000
= 345,000 calories
what is the temperature of 0.750 of a gas stored in a 6,850 mL cylinder at 2.21 atm?
why does ocean water found near the poles often have a higher leaves of salinity than ocean water found near the equator
The ocean water found near the poles has a higher level of salinity because the area of rain reduces as one moves toward the poles, and as a result of less rain and more sunshine, evaporation increases.
What is salinity?Salinity is the presence of salt in the water. Freshwater bodies have very less amount of salt, but ocean water has a large amount of salt dissolved in it.
Because cold polar air cools the water and decreases its temperature, raising its salinity, water close to the poles frequently has more salinity. When fresh water freezes out of seawater to form sea ice, the salinity of the remaining water likewise rises.
Therefore, as one travels toward the poles, the area of rain decreases, and as a result of less rain and more sunshine, evaporation increases, and the ocean water there has a higher level of salinity.
To learn more about salinity, refer to the link:
https://brainly.com/question/11798887
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what are causes of students to drop-out from university
Answer:
stress
Explanation:
people cn get stressed and not want to do work
In an experiment, the molar mass of the compound was determined to
be 228.276 g/mol. What is the molecular formula of the compound? Please help!
When 2 equal forces act on and object and the object generally doesn't move is
A. interia
B. unbalanced force
C. balanced force
D. speed
Answer:
a balanced force since the object isn't moving
hope this helped
Prometheus is a character that stole fire from the gods in Greek mythology. Which element is named from Prometheus?
Answer:
Promethium
Pm 61
Discovered by Jacob .A. Marinsky